Routing - Semaphore Group of · PDF fileA distance-vector routing protocol requires that a router informs its neighbors of topology changes periodically and, in some cases, when a

Semaphore Technologies Pvt. Ltd. – ([email protected])


ROUTING

Define Routing? In internetworking, the process of moving a packet of data from source to destination. Routing is usually performed by a dedicated device called a router. Routing is a key feature of the Internet because it enables messages to pass from one computer to another and eventually reach the target machine. Each intermediary computer performs routing by passing along the message to the next computer. Part of this process involves analyzing a routing table to determine the best path.

Routing is often confused with bridging, which performs a similar function. The principal difference between the two is that bridging occurs at a lower level and is therefore more of a hardware function whereas routing occurs at a higher level where the software component is more important. And because routing occurs at a higher level, it can perform more complex analysis to determine the optimal path for the packet.

Static vs. Dynamic Routing

Routing can be accomplished by manually entering the information necessary for packets to reach any part of the internet work into each router. This is called static routing.

Static routing works reasonably well for very small networks, but does not scale well. When using static routing, the routing tables on each router must be updated each time the network topology changes -- such as when a network link fails.

In most networks, routing is managed automatically through the use of dynamic routing. In dynamic routing, routing protocols create and maintain the routing tables automatically. Dynamic routing responds much more quickly to network changes (and network failures) than static routing.

Creating a Static Route under UNIX Under UNIX, static routes can be created using the `route` command. The example shows the creation of a static route for a single host:



# route add 193.252.19.5 192.252.19.1 add net 193.252.19.5: gateway 192.252.19.1 We can see the static route which was created using the `netstat -nr` command: # netstat -nr Routing tables Internet: Destination Gateway Flags Refs Use Netif Expire ... 193.252.19.5 193.252.19.1 UGS 0 0 fxp0 .. Creating a Static Route under Cisco IOS To add a static route on a Cisco router, use the `ip route` command. The syntax to utilize is: ip route &ltdestination> <netmask> <next hop>. The example shows the creation of a static route for a single host: FAQ-Cisco# conf t FAQ-Cisco (config)# ip route 193.252.19.5 255.255.255.255 193.252.19.1 Interior vs. Exterior Routing Protocols Some routing protocols are designed for use within an organization, while other routing protocols are designed for use between organizations. The current lead Interior Gateway Protocol (IGP) is OSPF. Other Interior Gateway Protocols include IS-IS, RIP, and EIGRP. The current lead Exterior Gateway Protocol is BGP. The current revision of BGP is BGP4. There are no other Exterior Gateway Routing protocols in current competition with BGP4. Distance Vector vs. Link State Routing Protocols Routing protocols such as RIP and EIGRP are Distance Vector routing protocols. These are called Distance Vector protocols because they base routing decisions on the "distance" of the remote destination in terms of the number of network layer hops which the packet will have to traverse. OSPF and IS-IS are Link State routing protocols. They are called Link State protocols because they base routing decisions on messages received from other routers in the internet work which give information about state of the links connected to them. Distance-vector routing protocol



A distance-vector routing protocol is one of the two major classes of routing protocols used in packet-switched networks for computer communications, the other major class being the link-state protocol. A distance-vector routing protocol uses the Bellman-Ford algorithm to calculate paths. Examples of distance-vector routing protocols include RIPv1 or 2 and IGRP. EGP and BGP are not pure distance-vector routing protocols but their concepts are the same. In many cases, EGP and BGP are considered DV (distance-vector) routing protocols. A distance-vector routing protocol requires that a router informs its neighbors of topology changes periodically and, in some cases, when a change is detected in the topology of a network. Compared to link-state protocols, which requires a router to inform all the nodes in a network of topology changes, distance-vector routing protocols have less computational complexity and message overhead. Link-state routing protocol A link-state routing protocol is one of the two main classes of routing protocols used in packet-switched networks for computer communications. Examples of link-state routing protocols include OSPF and IS-IS. The link-state protocol is performed by every switching node in the network (i.e. nodes which are prepared to forward packets; in the Internet, these are called routers). The basic concept of link-state routing is that every node receives a map of the connectivity of the network, in the form of a graph showing which nodes are connected to which other nodes. Each node then independently calculates the best next hop from it for every possible destination in the network. (It does this using only its local copy of the map, and without communicating in any other way with any other node.) The collection of best next hops forms the routing table for the node. This contrasts with distance-vector routing protocols, which work by having each node share its routing table with its neighbors. In a link-state protocol, the only information passed between the nodes is information used to construct the connectivity maps. The 7 Layers of the OSI Model The OSI, or Open System Interconnection, model defines a networking framework for implementing protocols in seven layers. Control is passed from one layer to the next, starting at the application layer in one station, and proceeding to the bottom layer, over the channel to the next station and back up the hierarchy.



Application (Layer 7)

This layer supports application and end-user processes. Communication partners are identified, quality of service is identified, user authentication and privacy are considered, and any constraints on data syntax are identified. Everything at this layer is application-specific. This layer provides application services for file transfers, e-mail, and other network software services. Telnet and FTP are applications that exist entirely in the application level. Tiered application architectures are part of this layer.

Presentation (Layer 6)

This layer provides independence from differences in data representation (e.g., encryption) by translating from application to network format, and vice versa. The presentation layer works to transform data into the form that the application layer can accept. This layer formats and encrypts data to be sent across a network, providing freedom from compatibility problems. It is sometimes called the syntax layer.

Session (Layer 5)

This layer establishes, manages and terminates connections between applications. The session layer sets up, coordinates, and terminates conversations, exchanges, and dialogues between the applications at each end. It deals with session and connection coordination.

Transport (Layer 4)

This layer provides transparent transfer of data between end systems, or hosts, and is responsible for end-to-end error recovery and flow control. It ensures complete data transfer.

Network (Layer 3)

This layer provides switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. Routing and forwarding are functions of this layer, as well as addressing, internetworking, error handling, congestion control and packet sequencing.

Data Link (Layer 2)

At this layer, data packets are encoded and decoded into bits. It furnishes transmission protocol knowledge and management and handles errors in the physical layer, flow control and frame synchronization. The data link layer is divided into two sub layers: The Media Access Control (MAC) layer and the Logical Link Control (LLC) layer. The MAC sub layer controls how a computer on the network gains access to the data and permission to transmit it. The LLC layer controls frame



synchronization, flow control and error checking. Physical (Layer 1)

This layer conveys the bit stream - electrical impulse, light or radio signal -- through the network at the electrical and mechanical level. It provides the hardware means of sending and receiving data on a carrier, including defining cables, cards and physical aspects. Fast Ethernet, RS232, and ATM are protocols with physical layer components.

Network Topology A network consists of multiple computers connected using some type of interface, each having one or more interface devices such as a Network Interface Card (NIC) and/or a serial device for PPP networking. Each computer is supported by network software that provides the server or client functionality. The hardware used to transmit data across the network is called the media. It may include copper cable, fiber optic, or wireless transmission. The standard cabling used for the purposes of this document is 10Base-T category 5



Ethernet cable. This is twisted copper cabling which appears at the surface to look similar to TV coaxial cable. It is terminated on each end by a connector that looks much like a phone connector. Its maximum segment length is 100 meters. Network Categories There are two main types of network categories which are:

• Server based • Peer-to-peer

In a server based network, there are computers set up to be primary providers of services such as file service or mail service. The computers providing the service are called servers and the computers that request and use the service are called client computers. In a peer-to-peer network, various computers on the network can act both as clients and servers. For instance, many Microsoft Windows based computers will allow file and print sharing. These computers can act both as a client and a server and are also referred to as peers. Many networks are combination peer-to-peer and server based networks. The network operating system uses a network data protocol to communicate on the network to other computers. The network operating system supports the applications on that computer. A Network Operating System (NOS) includes Windows NT, Novell Netware, Linux, UNIX and others. Three Network Topologies The network topology describes the method used to do the physical wiring of the network. The main ones are bus, star, and ring.



1. Bus - Both ends of the network must be terminated with a

terminator. A barrel connector can be used to extend it. 2. Star - All devices revolve around a central hub, which is what

controls the network communications, and can communicate with other hubs. Range limits are about 100 meters from the hub.

3. Ring - Devices are connected from one to another, as in a ring. A data token is used to grant permission for each computer to communicate.

There are also hybrid networks including a star-bus hybrid, star-ring network, and mesh networks with connections between various computers on the network. Mesh networks ideally allow each computer to have a direct connection to each of the other computers. The topology this documentation deals with most is star topology since that is what Ethernet networks use.





Three-Layer Hierarchical Model Most of us were exposed to hierarchy early in life. Anyone with older siblings learned what it was like to be at the bottom of the hierarchy. Regardless of where you first discovered hierarchy, today most of us experience it in many aspects of our lives. It is hierarchy that helps us understand where things belong, how things fit together, and what functions go where. It brings order and understandability to otherwise complex models. If you want a pay raise, for instance, hierarchy dictates that you ask your boss, not you’re subordinate. That is the person whose role it is to grant (or deny) your request. So basically, understanding hierarchy helps us discern where we should go to get what we need. Hierarchy has many of the same benefits in network design that it does in other areas of life. When used properly, it makes networks more predictable. It helps us define which areas should perform certain functions. Likewise, you can use tools such as access lists at certain levels in hierarchical networks and avoid them at others. Let’s face it; large networks can be extremely complicated, with multiple protocols, detailed configurations, and diverse technologies. Hierarchy helps us summarize a complex collection of details into an understandable model. Then, as specific configurations are needed, the model dictates the appropriate manner to apply them. The hierarchical model can help you design, implement, and maintain a scalable, reliable, cost-effective hierarchical internet work and defines three layers of hierarchy, as shown in the Figure each with specific functions.



The following are the three layers and their typical functions:

• The core layer: Backbone • The distribution layer: Routing • The access layer: Switching

Each layer has specific responsibilities. Remember, however, that the three layers are logical and are not necessarily physical devices. Consider the OSI model, another logical hierarchy. The seven layers describe functions but not necessarily protocols, right? Sometimes a protocol maps to more than one layer of the OSI model, and sometimes multiple protocols communicate within a single layer. In the same way, when we build physical implementations of hierarchical networks, we may have many devices in a single layer, or we might have a single device performing functions at two layers. The definition of the layers is logical, not physical. Now, let’s take a closer look at each of the layers. IP Addressing One of the most important topics in any discussion of TCP/IP is IP addressing. An IP address is a numeric identifier assigned to each machine on an IP network. It designates the specific location of a device on the network. An IP address is a software address, not a hardware address—the latter is hard-coded on a Network Interface Card (NIC) and used for finding hosts on a local network. IP addressing was designed to allow a host on one network to communicate with a host on a different network, regardless of the type of LANs the hosts is participating in. Summary of the three classes of networks:



Private IP Addresses The people who created the IP addressing scheme also created what we call private IP addresses. These addresses can be used on a private network, but they’re not routable through the Internet. This is designed for the purpose of creating a measure of well-needed security, but it also conveniently saves valuable IP address space. If every host on every network had to have real routable IP addresses, we would have run out of IP addresses to hand out years ago. But by using private IP addresses, ISPs, corporations, and home users only need a relatively tiny group of bona fide IP addresses to connect their networks to the Internet. This is economical because they can use private IP addresses on their inside networks and get along just fine. To accomplish this task, the ISP and the corporation—the end user, no matter who they are—need to use something called a Network Address Translation (NAT), which basically takes a private IP address and converts it for use on the Internet. Many people can use the same real IP address to transmit out onto the Internet. Doing things this way saves megatons of address space—good for us all! Reserved IP Address Space

Public IP Addresses Public IP Addresses (also known as Static IP Addresses) are IP addresses that are visible to the public. Because they are public, they allow other people to know about and access your computer, like a Web server. In some cases, you do not want people to access your computer or you want to restrict certain individuals from accessing your computer or server. If that is the case, you will want to look into security measures to protect your computer.



Subnetting Basics We learned how to define and find the valid host ranges used in a Class A, Class B, and Class C network address by turning the host bits all off and then all on. This is very good, but here’s the catch: You were only defining one network. What happens if you wanted to take one network address and create six networks from it? You would have to do something called subnetting, because that’s what allows you to take one larger network and break it into a bunch of smaller networks. There are loads of reasons in favor of subnetting. Some of the benefits include:





Reduced network traffic We all appreciate less traffic of any kind. Networks are no different. Without trusty routers, packet traffic could grind the entire network down to a near standstill. With routers, most traffic will stay on the local network; only packets destined for other networks will pass through the router. Routers create broadcast domains. The smaller broadcast domains you create the less network traffic on that network segment. Optimized network performance This is a result of reduced network traffic. Simplified management It’s easier to identify and isolate network problems in a group of smaller connected networks than within one gigantic network. Facilitated spanning of large geographical distances Because WAN links are considerably slower and more expensive than LAN links, a single large network that spans long distances can create problems in every arena listed above. Connecting multiple smaller networks makes the system more efficient. Cisco Routers for Small, Midsized and Large Businesses

Product Portfolio (http://www.cisco.com)

1. Cisco 12000 Series Routers 2. Cisco 10700 Series Routers 3. Cisco 10000 Series Routers 4. Cisco 7600 Series Routers 5. Cisco 7500 Series Routers 6. Cisco 7300 Series Routers 7. Cisco 7200 Series Routers 8. Cisco 3800 Series Integrated Services Routers



9. Cisco 3700 Series Multiservice Access Routers 10. Cisco 3600 Series Multiservice Platforms 11. Cisco 3200 Series Wireless and Mobile Routers 12. Cisco 2800 Series Integrated Services Routers 13. Cisco 2600 Series Multiservice Platforms 14. Cisco 1800 Series Integrated Services Routers 15. Cisco 1700 Series Modular Access Routers 16. Cisco 800 Series Routers 17. Cisco Carrier Routing System 18. Cisco Catalyst 6500 Series Switches 19. Cisco IOS XR Software 20. Cisco MWR 1900 Mobile Wireless Routers 21. Cisco Power Supplies 22. Cisco Router and Security Device Manager 23. Cisco SB 100 Series Small-Business Routers 24. Cisco SOHO 90 Series Secure Broadband Routers 25. Cisco SOHO 70 Series Routers 26. Cisco XR 12000 Series Router

Compare Products and Solutions Series Features

Cisco Catalyst 6500 Series Switches

• The Catalyst 6500 Series Switches are an integral part of the routing portfolio, extending services from the campus to the WAN edge

• Ideal for convergence of data center, campus, and WAN in a single system

• High-performance switching and full WAN functionality in one chassis

• End-to-end application intelligence and resilient WAN services

Cisco 7600 Series Routers

• Ideal for enterprise wide-area or metropolitan-area network aggregation or service-provider environments

• Business-class security supports services modules including IPSec, firewall, SSL VPN, and IPS

• Supports up to four slots for redundant supervisors and line cards; 6-, 9-, and 13-slot chassis available

• Support for up to 12 Shared Port Adapter (SPA) bays and SPA Interface Processors (SIP) for intelligent services

• Application versatility supports managed network services, WAN and broadband aggregation, MPLS, VPN, QoS, and multiservice environments

• Business-class security includes stateful inspection firewall, software and hardware



Cisco 7200 Series Routers VPN encryption, service-level validation features, and intrusion detection

• Multiservice data/voice features include analog and digital voice, Survivable Remote Site Telephony, and multiservice interchange (MIX)-enabled backplane

Cisco 3800 Series Integrated Services Routers

• Designed for medium-sized to large businesses and enterprise branch offices

• Wire-speed performance with services enabled at up to T3/E3 rates; increased services density for security, voice, caching, video, network analysis, and L2

• Security features include hardware-based VPN acceleration, antivirus defense through Network Admission Control, IPS, and SDM support


• Designed for small to medium-sized businesses and enterprise branch offices

• Wire-speed performance up to multiple T1/E1/ xDSL rates, increased services density for security, voice, caching, video, network analysis, and L2; and switching

• Security features include hardware-based VPN acceleration antivirus defense, IPS, and SDM support


• Designed for small to medium-sized businesses and small enterprise branch offices

• Available in both fixed and modular configurations

• Wire-speed performance with secure data services enabled at up to T1,E1, or xDSL rates

• Business-class security with stateful firewall with URL filtering, VPN 3DES encryption and Advanced Encryption Standard (AES), Dynamic Multipoint VPN, IPS, and secure wireless LAN option

• Secure WLAN option for simultaneous 802.11a and 802.11b/g operation with use of multiple antennas



Cisco 800 Series Routers

• Ideal for small offices and teleworker deployments

• Manageability and reliability of Cisco IOS Software

• Fixed configuration with support for a wide variety of WAN interfaces

• Business-class security with stateful inspection firewall, VPN 3DES encryption, IPS, and AES encryption

• Secure WLAN 802.11b/g option

Cisco SB100 Series Routers

• Designed for small businesses • Fixed configuration with manageability

and reliability of Cisco IOS Software • Asymmetric DSL (ADSL), ADSL over

ISDN, or an Ethernet WAN interface with a four-port 10/100 switch

• Basic security with stateful inspection firewall

Juniper Networks Product Portfolio Diagram (http://www.juniper.net) Application Acceleration platforms

These secure application acceleration platforms also provide assured application delivery. Organizations benefit from productivity gains realized across the full gamut of business applications, including web

enabled applications, regardless of a user's location. Circuit to Packet

These CTP-series products have the advanced technology and features required to reliably transport circuit-based applications across a new generation of IP networks. The products offer field-proven flexibility,

performance and reliability for circuit applications. E-series

Find out how Juniper Networks next-generation edge routing platforms help accommodate carrier requirements at the Infranet broadband edge.

J-series J-series routers are forward-looking platforms with performance headroom and extensible memory to meet future demands. They also deliver unmatched performance, investment protection and reliability for

remote, branch and regional offices. M-series



Find out how Juniper Networks Service-built M-series meet the demands of the Infranet multiservice edge with secure, dependable, cost-efficient solutions.

T-series Find out how Juniper Networks continues rejuvenating the Infranet core with T-series platforms, offering cost-efficient scalability with rich, dependable services.

MX-series Find out how Juniper Networks optimizes Ethernet network architectures and services.

JUNOS JUNOS software helps customers transform their IP infrastructure into an Infranet – the service provider's road to sustained economic success.

SDX Service Deployment System Find out how Juniper Networks Service Deployment System (SDX 300) delivers a rich suite of troubleshooting tools to quickly identify and correct service-threatening impairments.

Juniper Networks Application Acceleration Platforms

Product Features

DX platforms

Incorporate critical security functionality and provide unprecedented web performance and application availability in an easy-to-manage, flexible platform. Web I/O processor speeds download times for modem and broadband users accessing static, dynamic, secure or clear content, significantly improving site usability and customer satisfaction

WX platforms

Provide a scalable approach to accelerating application performance, increasing WAN capacity, and enabling application prioritization and visibility. The WX platforms deliver compressed and accelerated output in speeds from 64 Kbps to 155 Mbps and support a range of connections to other WX and WXC devices.



Product Features

WXC platforms

In addition to the WX platforms benefits, the WXC products include on-board hard drives to store repeated data patterns, increasing WAN capacity by as much as 100x. The WXC platforms support disk capacity from 40 GB to 3 TB and WAN links from 128 Kbps to 155 Mbps.

Juniper Networks Circuit to Packet

• Juniper Networks circuit to packet products reliably transport circuit based applications across a new generation of IP networks

• Software-selectable interfaces include T1, E1, EIA-530, RS-232, V.35 and 4WTO

• Comprehensive Web-based management for provisioning, troubleshooting, monitoring and graphing real time and historic performance information

Juniper Networks E-series Broadband Service Routing Platform

• Carrier-class routing with wire-speed performance • Comprehensive subscriber management and IP service support • Sophisticated, dynamic QoS implementation optimized for multiplay service

delivery to business and residential customers • Low operational costs and consistent services, with a single JUNOSe image

across all platforms and policy-based control via seamless integration with the Session and Resource Control portfolio



Juniper Networks J-series Services Routers

• J-series services routers include the most advanced set of mechanisms for fully protecting routers from outside threats

• A full, rich set of IPv4 and IPv6 features and routing protocols combined with the broadest MPLS features available

• Comprehensive range of interfaces supporting serial, T1/E1, Fast Ethernet, DS3/E3, ISDN, ADSL2/2+, G.SHDSL and Gigabit Ethernet

• JUNOS software delivers high levels of resiliency, stability and uptime Juniper Networks M-series Multiservice Edge Routing Portfolio

• M7i, M10i, M20, M40e, M120, M320 multi-service edge routers • Multi-service edge router delivering any Layer 2 or Layer 3 service to any

customer • Low operational costs and consistent services, with a single JUNOS image

across all platforms and policy-based control via SDX-300 • IP/MPLS services that scale with proven stability in the world's largest high-

performance networks Juniper Networks T-series Core Platforms

• Includes T320, T640, TX Matrix and T1600



• Proven solutions that leverage production-hardened JUNOS software • Flexible in-service upgrade paths • Industry leading density

Juniper Networks MX-series Ethernet Services Routers

• Performance at scale - New Dense Port Concentrators (DPC) cards combine high port density with a distributed architecture and on-board processing.

• Advanced QoS - Superior QoS at the interface level, enabling providers to ensure services receive the appropriate level of quality regardless of traffic conditions.

• Service flexibility - Leverages the JUNOS operating system. JUNOS Network Operating System

• One operating system with a single source base of code and a single

implementation for each feature • Single software release train extended through a highly disciplined and firmly

scheduled development process • Common modular software architecture that scales across all JUNOS™

platforms Juniper Networks SDX

• Offer highly scalable, advanced IP services including video on demand • Individualize and enhance the customer experience • Rapidly create and deploy a raft of new revenue-generating services



NORTEL PRODUCTS: (http://www.nortel.com) Customer Contact • Computer

Telephony Integration (CTI)

• IP Contact Center • Multimedia

Customer Contact • Self-Service LAN, MAN & WAN • Application

Switching & Optimization

• Ethernet & Metro Routing Switches

• Multiservice Switches

• Network Management

• Secure Routers • WLAN

Optical Networks • Multiservice

SONET/SDH • Network

Management • Optical Ethernet • Optical Switches • Storage

Connectivity • WAN Optimization • Wavelength Division

Multiplexers Phones, Clients & Accessories • Business Series

Phones • Digital Phones • IP Phones & Clients • Wireless Phones Security & VPN • Firewalls • Intrusion Prevention • Network Access

Control • Network

Management • Security • VPN

Voice, Multimedia & Unified Communications • Communication &

Application Servers • Digital Voice Switches • IP Multimedia

Subsystem (IMS) • IP-Enabled & Pure IP

Carrier Networks • IP-Enabled & Pure IP

Enterprise Networks • Network Management • PBXs & Key Systems • Services & Applications • Wireless for SMB Wireless Networks • CDMA Networks • GSM & UMTS Networks • IP Multimedia

Subsystem (IMS) • Municipal Wireless • WLAN • WiMAX • Wireless Mesh

CUSTOMER PRODUCTS AND SOLUTIONS: There's a revolution going on in the workplace and Nortel is leading the charge, with secure, reliable voice, video and data communications solutions that will forever change the way you do business. Hundreds of millions of people around the world count on us each day to keep their communications protected and connected - to their workplace and to each other. See what Nortel can do for you to achieve your business goals.

Large Enterprises Small & Medium Business Government Industries

Service Providers Cable Operators Wireless Operators

Large Enterprises Every enterprise faces a unique set of challenges that can't be solved either with a one-off or a pre-packaged approach. Challenges like reducing operating costs, simplifying management and administration and keeping a worldwide workforce



connected require a tailored solution that takes into account your existing systems, as well as what you want to do in the future. We work with you at your pace -- not ours -- to provide the solutions to help your business grow. Just ask any of the 450 companies in the Fortune 500 who are trusting Nortel to keep their day-to-day operations running smoothly and securely. Small & Medium Business Whether your network serves 10, 100, 500 or more employees, you need a communications solution that delivers business value and can evolve as your company evolves -- without sacrificing current technology investments. Nortel has these solutions. One out of every five small/medium businesses already has a Nortel communications systems delivered and supported by our expert channel partners. More than 16 million professionals worldwide can't be wrong. Government Whether on the federal, state or local level, governments are held accountable by their constituents to keep communications secure, respond quickly, improve public safety, operate efficiently and cut costs whenever possible - all without compromising current infrastructure investments. You'll find Nortel embedded in the communications network of the governments around the world including the U.S. Department of Defense. Our experience means that our government solutions portfolio is among the best in the industry. Service Providers In a crowded market like telecommunications, everyone is looking for that little something extra that will give them a competitive edge. To every one of the top 25 service provider networks globally, Nortel is that little something extra. We can improve your ranking in the marketplace, too. Cable Operators Imagine the ability to leverage someone else's R&D team to help you generate new revenue, keep up with ever-changing cable applications, Packet Cable standards and adapt your network for new traffic. Because of our commitment to the cable industry, Nortel does just that for you. Wireless Operators Wireless voice and data communications are evolving on a daily, if not hourly, basis, and only those operators who can keep up will ultimately survive. Nortel has the solutions you need to stay in the game, regardless of access choice - CDMA, GSM/GPRS/EDGE, WiMAX, LTE, UMB, and WiFi. With billions of wireless calls depending on Nortel each year and over 300 wireless networks deployed in over 70 countries...we know wireless networks and we know how to meet your business needs.



3com PRODUCTS: (http://www.3com.com) Product Offerings by Product Category 3Com Security Solutions Convergence/IP Telephony LAN Switches (IntelliJack® Switches) LAN Switches (Modular) LAN Switches (Stackable/Edge) LAN Transceivers / Cables

Maintenance Services Network Interface Cards Network Management Professional Services Routers Wireless

SWITCHES:

IntelliJacks Switches Unmanaged Switches OfficeConnect Switches OfficeConnect Managed Switches Baseline Switches Baseline Plus Switches Unified Switch Switch 4200 Switch 4200G Switch 4500 Switch 4500G Switch 5500/5500G Switch 7750 Switch 8800

ROUTERS:

Router 3000 Router 3000 DSL OfficeConnect Routers Router 5000 Router 6000

SECURITY: Intrusion Prevention Systems

3CRTP0050C96C 3CRTP0200C96C 3CRTP0200EC96 3CRTP0400C96C 3CRTP0400CF96C 3CRTP0400F96C 3CRTP1200EC96 3CRTP1200EF96



3CRTP1200ECF96 3CRTP2400EC96 3CRTP2400EF96 3CRTP2400ECF96 3CRTP5000C96D 3CRTP5000F96D 3CRTP5000CF96D

Integrated Security Systems 3CRTPX505-73

Security Management Systems 3CRTP000096C 3CRTP000196C 3CRTP000296C 3CRTP000396C

WIRELESS: Wireless Bridges Wireless Access Points Wireless Switches Wireless NICs IP PHONES:

3C10399A 3C10401B 3C10401SPKRB 3C10402B 3C10403B 3C10405B 3C10406A 3C10407A 3C10408A

D-LINK PRODUCT CATAGORIES: (http://www.dlink.com) Cable/DSL Routers



DAX (http://daxnetworks.com) Networking Products Switches

Dax provides a wide range of switches for SOHO and corporate users. Dax switch range includes unmanaged, enhanced, managed, stackable and backbone switches with or without modular options. Dax switches are available in Desktop, Palm and Rack mountable size.

The salient features of Dax switches include increased network performance, increased availability of network resources, flexibility/ scalability, decreased packet loss and reduced workload on individual clients/nodes.

Structured Cabling

WHAT IS STRUCTURED CABLING?



Structured cabling is a “standards” based method of engineering and installing an integrated data, voice and video cabling system for your business. A properly designed and installed structured cabling system provides you with a cabling infrastructure that delivers predictable performance as well as flexibility to accommodate growth and change over an extended period of time. Additionally, a structured cabling system provides a uniform, open physical cabling topology that can simultaneously support multiple logical networking topologies for different networking applications such as Ethernet and ATM. Your initial investment in a “standards” based structured cabling system will return many benefits including an extended operational lifespan, predictable performance, manageability and growth. These benefits bring increased efficiency, improved productivity and reduced costs to you and to your business.

WHAT ARE “STANDARDS” AND WHY ARE THEY IMPORTANT?

Domestic and international standards organizations have been formed to ensure that manufactured products meet certain quality, safety and performance “norms” for that category and class of product. Standards organizations such as ISO/IEC, TIA/EIA, CENELEC and CSA have created and published standards for structured cabling products and systems, and their specifications for Category 5, Category 5e and proposed specifications for Category 6 systems are widely used and accepted in the industry today.

For end-users, the challenge will be in selecting a structured cabling system that will meet both current and future needs. Whether those needs indicate the use of Category 5, Category 5e or Category 6 systems, end-users should look for systems that not only meet but exceed the specifications of each respective standard, thereby providing additional performance margins to accommodate the evolution of ever more demanding networking needs.

Routers

A router translates information from one network to another and it is similar to a super-intelligent bridge. Routers select the best path to route a message, based on the destination address and origin. It can direct traffic to prevent head-on collisions, and is smart enough to know when to direct traffic along back roads and shortcuts. While bridges know the addresses of all computers on each side of the network, routers know the addresses of computers, bridges, and other routers on the network.

Routers can even "listen" to the entire network to determine which sections are busiest - they can then redirect data around those sections until the clear up. If you have a school LAN that you want to connect to the Internet, you will need to purchase a router.

In this case, the router serves as the translator between the information on your LAN and the Internet. It also determines the best route to send the data over the Internet.



Routers can direct signal traffic efficiently, route messages between any two protocols, route messages between linear bus, star, and star-wired ring topologies route messages across fiber optic, coaxial, and twisted-pair cabling.

Routers direct data packets conforming to any of a variety of network protocols or network operating systems from one network to another.

In addition to passing data packets between LANs or LAN segments, routers can determine the most efficient path through the network and forward data packets along that path to boost network performance.

Routers function as intelligent, high-speed bridges, and as such, bear higher costs than traditional bridges. Routers examine data packets flowing through them and determine the packet's protocol and its destination, determining if the two are compatible. Because of their rich feature set, which requires significant processing power, routers can also be the source of network bottlenecks.

Routers can be important to an enterprise networking strategy because they can intelligently deliver data to distinct geographically distributed networks devoted to particular business functions.

Packets are only passed to the network segment they are destined for. They work similar to bridges and switches in that they filter out unnecessary network traffic and remove it from network segments. Routers generally work at the protocol level. Routers were devised in order to separate networks logically.

Most routers can also perform bridging functions. A major feature of routers, because they can filter packets at a protocol level, is to act as a firewall. This is essentially a barrier, which prevents unwanted packets either entering or leaving the network.

Wireless LAN

Wireless LAN technology is gaining broad acceptance and being adopted worldwide in organizations that clamor for the competitive advantage of an increasingly mobile and highly productive workforce.

Before going wireless, organizations understandably have many questions. For instance, what are the current options for wireless LAN technology? What is the state of effort to standardize these technologies? Will the newest wireless devices be backward compatible and ensure protection for future wireless investments?

This technology guide addresses those issues, answering the pressing questions that will help you make a more informed decision about wireless technology for your organization. The guide introduces Wireless Access Point, which sets the enterprise standard for secure, manageable, and reliable wireless LANs while also providing a smooth migration path to future high-speed wireless LAN technologies. This innovative, state-of-the art wireless infrastructure platform features dual-band functionality that simultaneously supports current and emerging wireless standards. One of the most innovative aspects of the Wireless Access Point is that it is both



software and hardware up gradable. Organizations can not only upgrade their software to take advantage of new features that DAX will develop in the future, but they also will be able to upgrade the radios in the field to take advantage of new high-speed wireless standards. With the Wireless Access Point, your organization can confidently implement wireless today-without worrying about incompatibility with future wireless technologies, protocols, and standards.

LAN Extender

A LAN extender is a remote-access multilayer switch that connects to a host router. LAN extenders forward traffic from all the standard network-layer protocols (such as IP, IPX, and AppleTalk), and filter traffic based on the MAC address or network-layer protocol type. LAN extenders scale well because the host router filters out unwanted broadcasts and multicasts. LAN extenders, however, are not capable of segmenting traffic or creating security firewalls. The below fig illustrates multiple LAN extenders connected to the host router through a WAN.

Remote Access Solutions

A Remote Access Server is a server, normally equipped with one or more modems, which allows remote users to dial in and establish temporary connections to a network. Sometimes called a communication server, a remote access server usually include or is associated with a firewall server to ensure security and a router that can forward the remote access request to another par of the corporate network.

Remote access is the ability to get access to a computer or a network from a remote distance. In corporation, people at branch offices, telecommuters, and people who are traveling may need access to the corporation's network. Home users get access to the Internet through remote access to an Internet service provider (ISP).



While Ethernet is limited to a geographic area, remote users such as traveling sales people need access to network-based resources. Remote LAN access, or remote access, is a popular way to provide this connectivity. RAS uses telephone services to link a user or office with an office network.

Typical Uses of RAS includes employee access to corporate Internet links from home and the road, employee access to corporate information in databases and on file servers, providing customer and vendor access restricted corporate information, such as order status or purchasing data, local dial-in access to your Web site or FTP server without the need for a Internet provider, and remote diagnostic and maintenance activities by system administrators.

The remote access server (RAS) platform is the foundation on which Internet service providers (ISP) and other telecommunications carriers are bringing to market integrated, Internet-based versions of traditional services such as voice over IP (VolIP), fax over IP (FaxIP), and data over IP.

In addition to supporting individual mobile users that require access to centrally located resources, dubbed PC-to-LAN communications, many remote access servers can also be configured like a bridge/router to link LAN-attached users at a branch site to a corporate Internet using dial-up links or dedicated lines, dubbed LAN-to-LAN communications.

The key disadvantage of remote access is tat it requires an additional investment in powerful remote computers and high-speed modems. And since applications run on the remote computer, the remote access method is not effective in supporting real-time databases.

Most of the remote access servers available in the market are scalable and rich in features. Several servers are built around modular chassis that can be reconfigured, as the remote-access needs change.

Virtual Private Dial-in Networking (VPDN) support can be found in most of the servers. Two technologies currently exist for providing VPDN support: the Point-to-Point Tunneling Protocol (PPTP) and the Layer 2 Forwarding (L2F) protocol. VPDN enables the remote users to connect through a local ISP account and, using encryption and encapsulation provided by PPTP and L2F creates a secure tunnel across the Internet to their agencies local networks.

In the security area, most RAS support remote authentication and other security requirement. Most of the servers provide client software for dial-in/dial-out and offer unlimited licensing for their use. PC remote access and remote control servers are another facets of the remote access market in that both enable the off-site users to utilize resources residing on a corporate network.

ISDN is a common method of remote access from branch offices since it combines dial-up with faster data rates. Wireless, cable modem, and DSL (Digital Subscriber Line) technologies offer other possibilities for remote access. ISDN is a special telephone service that offers three channels, two 64Kbps "B" channels for user data and a "D" channel for setting up the connection. With ISDN, the B channels can be combined for double bandwidth or separated for different applications or users.



The PC remote access method lets a user to attach to any file server on the network while the remote control method is designed to enable a remote user to take full control over a device residing on a central LAN. In the latter case, all application processing is done at the central host residing on a central LAN. In the latter case all application processing is done at the central host site, which handles all data requests on behalf of the remote computer and interacts, with other network resources; only keyboard strokes and screen updates get passed across the Wide Area Network (WAN) link.

Driven by these compelling market conditions, a new universal post-enabled generation of RAS equipment has emerged that provides the ability to support voice, fax, and modem services over nearly any packet-switched network.

The convergence of voice and data has resulted in a new generation of RAS equipment that provides universal port capabilities. The increasing demand for Internet access requires RAS equipment manufacturers to increase the density of their equipment dramatically. This is being facilitated by a new generation of DSP's with integrated voice-, fax-, and data-over-packet software that offer unprecedented processing power while providing very-low-power consumption.

Remote Access Servers (RAS), the hardware and software that allow the mobile users remotely access a corporate network, come in a wide range of prices and intricacies. Whatever the company's networking needs are, there is a RAS solution to meet them.

One must decide whether one needs extra security protocols, powerful management software expandability options or features, such as virtual networking and support for high-speed modem in the RAS one is looking for.

Voice/Speech/Conference Offering digital and analog network interfaces combined with rich, high-performance media processing characteristics, the Diva Server V-Series telephony adapters are key building blocks for enabling a new breed of voice business applications. Based on the latest PCI industry standards each adapter provides connectivity to the telephony network via Analog Trunk, ISDN Base Rate (BRI), Primary Rate (PRI), E1 or T1 interfaces. Powerful onboard Digital Signal Processor (DSP) resources - dedicated to each communication channel, ensure real-time voice processing and thus reduce latency and improve overall system performance for sophisticated, high-density speech solutions. Media Convectors The Media Converters become a mandatory part of large campus networks given the multiple media choice and complexity of today’s networks. The Media converters help in updating, expanding and optimizing network performance in mixed media switched environments. The highlight of the Dax Media Converters range is, its unique Media Converter chassis (DX-MC-16), which can accommodate 16 different types of media converters. Once installed, the media converters are hot swappable to avoid network downtime. The device is powered by a simple universal power supply, eliminating the need for



multiple power connections. Today Dax Networks gives you a wide choice of media converters, which can cater to all your media conversion, needs. Network Interface Cards DAX Ethernet PCI cards are specifically designed to meet today's growing demands for feature-rich solutions that deliver unparalleled scalability in speed, bandwidth and Quality of Service (QoS). Ideally suited for server farms, backbones and high-powered workstations where speed and efficiency are critical. Interface Convector

Interface converters are single port converters which converts one form of signals in to a required format to be connected with routers directly. The DX Series interface converter converts signals between G703 and V.35/Ethernet standards. Its compact size and

Low cost makes it ideal for cost-sensitive bridging applications or as a LAN extender over bit stream type infrastructures. Its E1 data interface also provides an economical digital access solution for E1 and Fractional E1 network Services, which can work at data rates of 64Kbps to 2048Kbps.

Modems

56K bps Download Speeds

When connected to a 56K Internet Service Provider POP compatible with your 56K chipset, your DAX 56K Modem will deliver the information to your computer at speed almost twice as fast as a lower speed modem. Check with your internet Service Provider for available connections.

33,600 bps Capable

Your DAX 56 K Modem is universally capable of up to 33,600 bps connection speeds and backward compatible with previous ITU-T standards.



Voice Features

The DAX 56 K modem is capable of full Voice operation, including an answering machine function, Speakerphone capable, and Digital Simultaneous Voice and Data transmission.

Windows 95 / 98 Plug and Play Compliant The DAX 56 K Modems are fully compliant with current Windows 95 / Windows 98.

Full Duplex Speakerphone on "V" Models Allows the user to speak hands free over the phone line via attached microphone (optional) and speaker (optional).

Complete Voice Mail and Telephone Answering capable Built-in technology allows for Modem to receive and take messages from incoming voice calls.

Software Packs Included

• Fax and Communications software • Internet Explorer - Microsoft's Internet Browser Software • And much more

Serial I/O Dax's extensive range of serial I/O makes it easy to add 4 to 512 serial ports to Linux, UNIX and Windows servers. Our serial I/O products provide the essential network connectivity between PCs/servers and peripheral devices. Management Tools



Introduction

The BATM/Telco Systems InterNetworking OS - BiNOS -embeds management intelligence in all BATM/Telco Systems hardware platforms. From the troubleshooter patching into a unit in the field, to the manager supervising the network from a central console, BiNOS supports administrators with performance information and configuration tools. BiNOS makes network management easy and intuitive.

Multilayer Switching Support

BiNOS-enabled network devices support advanced multilayer switching protocols. They can be field upgraded to higher-layer functionality - with no downtime in most cases.

Choose Your Tools

To exploit the management intelligence BiNOS puts in our devices, BATM/Telco Systems offers a complete range of command-line and graphical system management tools. Built around open SNMP standards, based on portable Java technology, these powerful tools integrate seamlessly with your existing network management toolkit.

Routers

Edge Routers

DaxDX-80XE series

Dax DX-1821

Dax DX-1841

Dax DX-2801

Dax DX-2811

Dax DX-3745

Dax DX-7208



Dax DX-7204

Dax DX-3725

Dax DX-3825

Documents

Routing - Semaphore Group of · PDF fileA distance-vector routing protocol requires that a router informs its neighbors of topology changes periodically and, in some cases, when a