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Outline
• Multicast
• Future Internet
• IPv6
• QoS
• Mobile IP
3
4
IGMP
Routing Protocols
Router
Router
Router
Router
Router
Router
Router
Router
Router
RouterRouter
5
Ethernet
Wireless or satellites (broadcast)
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Addresses
IGMP
Routing algorithms
Present solutions - protocols
Source Specific Multicast (SSM)
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0 netid hostid
1 0 netid hostid
1 1 0 netid hostid
1 1 1 0 multicast address
1 1 1 1 uso futuro
0 1 8 16 24 32
Classe A
Classe B
Classe C
Classe D
Classe E
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Internet Group Message Protocol
Router
Router
Router
Router
Router
Router
Router
Router
Router
RouterRouter
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Flooding
Spanning Trees
Reverse –Path Forwarding
RPF e Prunes
Steiner Trees
Center-Based Trees
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◦ To route the data only to multicast members;
◦ Optimized routes from the sources to destinations;
◦ No loops;
◦ Distributed routes;
◦ Support dynamic members.
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Easy to implement
Simple
Use of resources
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B
C
A
D
F
E
3
3
7
1
4
1
5
13
B
C
A
D
F
E
3
3
7
1
4
1
5
B
C
A
D
F
E
1
5
6
2
4
3
7
B
C
A
D
F
E
1
5
6
2
4
3
7
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Prune messages
Algorithm
Periodic messages
Dynamic groups
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Prune messages
Graft messages
Dynamic groups
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B
C
A
D
F
E
1
5
6
2
4
3
7
B
C
A
D
F
E
1
5
6
2
4
3
7
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Tree with a central node
Join and leave messages (IGMP)
Less information
Unidirectional and bi-directional trees
Problem: centre !
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Dense-mode
Sparse-mode
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Distance-vector
RPF
Tunnels
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Ethernet
A B
C
Ethernet
Ethernet
A B
C
D
RPF, prune and graft
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B
C
A
D
F
E
1
5
6
2
4
3
7B
C
A
D
F
E
1
5
6
2
4
3
7
CBT
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PIM-SM
Multicast Source Discovery Protocol
Multicast Border Gateway Protocol
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Different ISPs
Compatibility of internal routing protocols
Address allocation
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IGMPv3
MLDv2
Allowed sources
Advantages
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8 4 4 112
11111111 Flags Scope Group ID
• Number of multicast addresses
• Multicast-Ready
• Address allocation
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Ordered transmission and without errors
TCP vs UDP
Reliable Muticast ◦ Unreliable
◦ Semireliable
◦ Reliable
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Statistically reliable (%)
K-reliable
Sufficiently reliable (timeouts)
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Source ordering
Total ordering
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It is necessary to maintain a list for all receivers that already received ACKs.
Only after receiving all ACKs (from all receivers) to a specific data block, the source will delete that block in memory.
ACKs explosion
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The source can implement timeout mechanisms
The performance of source-initiated protocols are dependent of the number of participants.
A multicast group with a large number of members implies a large number of positive ACKs, and a large number of NACKs in instable environments,
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When a receiver detects that it doesn’t receive a packet, it must wait a random period and sends a NACK to the source and to all receivers.
This procedure reduces the number of NACKs in the system.
This procedure can only be applied in small networks (where the number of participants is low).
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Tree Ring These protocols require less memory, the
source doesn’t need to be aware of all receivers and the system is not dependent of the number of participants.
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The missing information is recovered by redundant information.
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Fragmentation/desfragmentation
Address/Routing
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32 bits
Networks ID
Host ID
Routing
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Dotted-decimal notation
Ex: 193.212.12.21
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Routing and management
Subnetting – Sub-network management
Ex: 223.1.1.0/24
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1)
IP address: 138.251.26.12
Subnet Mask: 255.255.255.0
Binary: 10001010.11111011.00011010.00001100
11111111.11111111.11111111.00000000
2)
IP address: 199.124.16.137
Subnet Mask: 255.255.255.192
Binary: 11000111.01111100.00010000.10001001
11111111.11111111.11111111.11000000
(Network 199.128.16.128, terminal 9)
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Binary Decimal
11111111.11111111.11111111.00000000 255.255.255.0
11111111.11111111.11111111.10000000 255.255.255.128
11111111.11111111.11111111.11000000 255.255.255.192
11111111.11111111.11111111.11100000 255.255.255.224
11111111.11111111.11111111.11110000 255.255.255.240
11111111.11111111.11111111.11111000 255.255.255.248
11111111.11111111.11111111.11111100 255.255.255.252
11111111.11111111.11111111.11111110 255.255.255.254
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0 netid hostid
1 0 netid hostid
1 1 0 netid hostid
1 1 1 0 multicast address
1 1 1 1 uso futuro
0 1 8 16 24 32
Classe A
Classe B
Classe C
Classe D
Classe E
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50 0 0 0 1 2 3 4 5 6 7 8 9
Numero do primeiro elemento
Identificador do Pacote
Mais fragmentos
50 0 1 0 1 2 3 4 5 6 7
Numero do primeiro elemento
Identificador do Pacote
Mais fragmentos
50 8 0 8 9
Numero do primeiro elemento
Identificador do Pacote
Mais fragmentos
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Source IP address
Header checksum
TOSVersion IHL
Time to live Protocol
Identification Fragment offset
Total length
Flags
Destination IP address
Options Padding
User data
20 bytes
4-40
bytes
32 bits
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VER (4 bits) ◦ Version (version 4)
IHL (4 bits) ◦ Internet Header Length – units of 4 bytes. By
default it is 5 (20 bytes). ◦ This is necessary as the header length is not
constant (options).
ToS (8bits) ◦ Type of Service
TL (16 bits) ◦ Total Length – datagram length (bytes),
header+data
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ID (16 bits) ◦ Identify the datagrams from the same segment.
Flag (3 bits) ◦ ―Don’t fragment‖ ◦ ―More fragments‖
FO (3 bits) ◦ Fragment position in the original datagram (unities of 8
bytes)
TTL (8 bits) ◦ Time To Live .
PROT (8 bits) ◦ Protocol
Header Checksum (16 bits)
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Rede
10.0.0.0Router A
Rede
20.0.0.0Router B
Rede
30.0.0.0Router C
Rede
40.0.0.0
10.0.0.5 20.0.0.5 20.0.0.6 30.0.0.6 30.0.0.7 40.0.0.7
Router B
Estação na rede Encaminhamento
20.0.0.0 Directo
30.0.0.0 Directo
10.0.0.0 20.0.0.5
40.0.0.0 30.0.0.7
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Address allocation poorly managed at the beginning
Solutions ◦ Address re-distribution (?)
◦ IPv6
◦ NAT
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Mapping of public addresses – private addresses ◦ 10.0.0.0 a 10.255.255.255 (1 network of
class A) ◦ 172.16.0.0 a 172.31.255.255 (16 networks
of class B) ◦ 192.168.0.0 a 192.168.255.255 (255
networks of class C)
NAT (using ports) ◦ Static ◦ Dynamic ◦ Overloading ◦ DHCP
Security support
Rede
Privada
Internet
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IANA – Internet Assigned Numbers Authority
Public addresses
Private addresses
NAT (Network Adress Translation)
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Adresses
Routing
Anycast
Auto-configuration
Multicasting
QoS support
Security
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Source IP address
Version
Next Header Hop limitPayload length
Flow label
40 bytes
32 bits
Traffic class
Destination IP address
Base HeaderExtension
Header 1
Extension
Header nData...
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Hop by Hop Options Header
Destination Options Header
Routing Header
Fragment Header
Authentication Header
Encapsulation Security Payload Header
IPv6 HeaderNext Header =
Routing
Routing
Header
Next Header =
TCPTCP Header Data
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v4: 196.132.204.12
v6:
196.132.204.12.196.132.204.12.196.132.204.12.196.132.204.12
fce0:a3c2:0000:2020:aa63:43a4:0000:a1a1
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TLA - Top-Level Aggregation Identifier RES - Reserved for future use NLA - Next-Level Aggregation Identifier SLA - Site-Level Aggregation Identifier Interface ID - Interface Identifier
Unicast
Multicast
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First bits Representation Type of address
00…0 (128 bits) ::/128 Não especificado
00…1 (128 bits) ::1/128 Endereço loop-back
11111111 FF00::/8 Endereços multicast
1111111010 FE80::/10 Endereços link-local
1111111011 FEC0::/10 Endereços site-local
restantes Endereços globais unicast
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Rede IPv 6
Rede IPv 6
Router
Router
IPv 4
IPv 4
IPv 4
IPv 4
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Data (e-mail, FTP, Telnet, WWW)
Audio (Voice over IP, Hi-fi)
Video (HDTV, VoD, videoconferencing)
Distributed processing (CAD, simulations)
Other (virtual reality, tele-medicine)
Applications
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What is it? ◦ Different levels of service for different types of
traffic Relevant parameters
Throughput
Delay
Jitter
Loss
◦ Fairness Competing traffic flows
Provide level of service according to SLAs
IP Quality of Service
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Isn't over-provisioning enough to solve IP QoS problems?
◦ Network resources (e.g., bandwidth) are not infinite
◦ Existing network resources are a trade-off between
cost/investment and performance
◦ There is the need to guarantee the agreed service level to applications, even when resources are not enough QoS is also a business opportunity
The need for quality of service
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How to guarantee that a network initially engineered for the support of elastic traffic (the Internet) can properly carry inelastic traffic?
The only networking technology designed from scratch for the
support of all types of traffic is ATM
How to guarantee that applications with different needs
get the resources they need (and that have paid for) even under global resource shortage?
How to guarantee fairness among different traffic flows?
IP QoS provision problems
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Throughput Peak rate
Mean rate
Delay Maximum delay
Delay variation (jitter, delay jitter)
Losses Due to congestion
Error rate
Needs of applications
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ITU-T Rec. G.114 defines three categories of applications in terms of end-to-end delay
Delay < 150 ms — acceptable delay for most applications
150 < delay < 400 ms — significant delay for some applications
Delay > 400 ms — unacceptable delay for most applications (namely telephony and conferencing)
Transit delay
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Acceptable loss/error rates
10-4 , for voice applications and file transfer applications
10-6 , for interactive data applications
10-7 , for image transfer applications
10-8 , for interactive compressed image transfer applications
Loss/Error rate
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Throughput
(Mbps)
De
lay
(ms
)
0.01 0.1 1 10 100 1000
1
10
100
1000
VoiceAudio
Hi-Fi
VoD/
Moving
images
HDTVVirtual
reality
Interactive
dataStill images
Intensive
data
Mainframe
interconn.
E-mailFile
transfer
Delay and throughput needs
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Data Network
Best-effort paradigm
New paradigms ◦ Integrated Services
◦ Differentiated Services
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Routers
Resource procedures
Individual and group flows
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Guaranteed Services (GS)
Controlled Load Services (CLS)
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Unicast / Multicast
IPv4 / IPv6
Soft-State
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Type of Service
Per Hop Behaviour (PHBs)
Service Level Agreement (SLAs)
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Router
Router
Router
Router
Router
Router
Router
Router
Router
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Layer 2
Layer 3
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HA
FA
Permanent address
Care-of-address
Foreign
Agent Home
Agent
Corresponding
node
Corresponding
Agent
Mobile
Node
1
2
3
74
Overcome the triangle routing problem
But adds complexity ◦ Learn the new COA ◦ Notify protocol to
the alert the CN ◦ Anchor foreign
agent
Foreign
Agent Home
Agent
Corresponding
node
Corresponding
Agent
Mobile
Node
1
2
3
4
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Organisations rely more and more on information processing
Networking plays a vital role in (distributed) information processing
There is a growing demand for bandwidth ◦ Increasing utilisation ◦ Many applications rely on high bandwidth consumption ◦ Information systems heavily rely on networking
IP networking is ubiquitous ◦ If applications are carried over IP they will also be
ubiquitous
IP Networking
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FA HA
CN
MN
Rede
Hospedeira
Rede
Base
Cabeçalho
OriginalNovo Cabeçalho
Pacote IP original
Source=HA
Dest=COASource)CN
Dest=MN
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Discovery Protocol
Registration Procedure
Encapsulation Procedure
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Sequence numbers
Life-Time
Flags
COAs
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Basic (RFC 2003)
Minimum (RFC2004)
Generic Routing Encapsulation (RFC 1701)
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128 bits addresses
Autoconfiguration ◦ Plug and Play
Low process in routers ◦ Path MTU Discovery
◦ Reduced routing tables
◦ Simplified headers
81
v4: 196.132.204.12
v6:
196.132.204.12.196.132.204.12.196.132.204.12.196.132.204.12
fce0:a3c2:0000:2020:aa63:43a4:0000:a1a1
82
Nodes mobile-ready
Redirects
There in no FA
