Cisco 4- Chapter 1

8/9/2019 Cisco 4- Chapter 1

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Chapter 1: Hierarchical Network Design

INTRODUCTION

Networks must meet the current needs of organizations

and be able to support emerging technologies as new

technologies are adopted. Network design principles and

models can help a network engineer design and build a

network that is e!ible" resilient" and manageable. This chapter introduces network design concepts"

principles" models" and architectures. It co#ers thebene$ts that are obtained b% using a s%stematic design

approach. &merging technolog% trends that will a'ect

network e#olution are also discussed.

(.( )ierarchical Network Design O#er#iew

(.(.( &nterprise Network Campus Design(.(.(.( Network Re*uirements

+hen discussing network design" it is useful to categorizenetworks based on the number of de#ices ser#iced,

• Small network - ro#ides ser#ices for up to /00de#ices.

• Medium-sized network - ro#ides ser#ices for

/00 to (000 de#ices.• Large network - ro#ides ser#ices for (0001

de#ices.Network designs #ar% depending on the size andre*uirements of the organizations. 2or e!ample" thenetworking infrastructure needs of a small organizationwith fewer de#ices will be less comple! than theinfrastructure of a large organization with a signi$cantnumber of de#ices and connections.

There are man% #ariables to consider when designing anetwork. 2or instance" consider the e!ample in the $gure.

The sample high-le#el topolog% diagram is for a largeenterprise network that consists of a main campus siteconnecting small" medium" and large sites.

Network design is an e!panding area and re*uires a greatdeal of knowledge and e!perience. The intent of thissection is to introduce commonl% accepted networkdesign concepts.Note, The Cisco Certi$ed Design 3ssociate 4CCD356 isan industr%-recognized certi$cation for network designengineers" technicians" and support engineers" whodemonstrate the skills re*uired to design basic campus"data center" securit%" #oice" and wireless networks.

(.(.(./ 7tructured &ngineering rinciples

Regardless of network size or re*uirements" a criticalfactor for the successful implementation of an% networkdesign is to follow good structured engineering principles.

These principles include,

• Hierarchy - 3 hierarchical network model is auseful high-le#el tool for designing a reliablenetwork infrastructure. It breaks the comple!problem of network design into smaller and moremanageable areas.

• Modularity - 8% separating the #arious functionsthat e!ist on a network into modules" the network iseasier to design. Cisco has identi$ed se#eralmodules" including the enterprise campus" ser#icesblock" data center" and Internet edge.

• esiliency - The network must remain a#ailablefor use under both normal and abnormal conditions.Normal conditions include normal or e!pected tra9cows and tra9c patterns" as well as schedulede#ents such as maintenance windows. 3bnormalconditions include hardware or software failures"

e!treme tra9c loads" unusual tra9c patterns"Denial-of-7er#ice 4Do76 e#ents" whether intentionalor unintentional" and other unplanned e#ents.

• !le"i#ility - The abilit% to modif% portions of thenetwork" add new ser#ices" or increase capacit%without going through a ma:or fork-lift upgrade 4i.e."replacing ma:or hardware de#ices6.

To meet these fundamental design goals" a network mustbe built on a hierarchical network architecture that allowsfor both e!ibilit% and growth.

(.(./ )ierarchical Network Design(.(./.( Network )ierarch%In networking" a hierarchical design in#ol#es di#iding the

network into discrete la%ers. &ach la%er" or tier" in thehierarch% pro#ides speci$c functions that de$ne its rolewithin the o#erall network. This helps the networkdesigner and architect to optimize and select the rightnetwork hardware" software" and features to performspeci$c roles for that network la%er. )ierarchical modelsappl% to both ;3N and +3N design.3 t%pical enterprise hierarchical ;3N campus networkdesign includes the following three la%ers,

• $ccess layer - ro#ides workgroup<user accessto the network.

• Distri#ution layer - ro#ides polic%-basedconnecti#it% and controls the boundar% between theaccess and core la%ers.

• Core layer - ro#ides fast transport betweendistribution switches within the enterprise campus.

The bene$t of di#iding a at network into smaller" moremanageable blocks is that local tra9c remains local. Onl%tra9c that is destined for other networks is mo#ed to ahigher la%er.;a%er / de#ices in a at network pro#ide little opportunit%to control broadcasts or to $lter undesirable tra9c. 3smore de#ices and applications are added to a atnetwork" response times degrade until the networkbecomes unusable.(.(././ 3ccess ;a%erIn a ;3N en#ironment" the access la%er grants endde#ices access to the network. In the +3N en#ironment"it ma% pro#ide teleworkers or remote sites access to thecorporate network across +3N connections.3s shown in the $gure" the access la%er for a smallbusiness network generall% incorporates ;a%er / switchesand access points pro#iding connecti#it% betweenworkstations and ser#ers.

The access la%er ser#es a number of functions including,

• ;a%er / switching

• )igh a#ailabilit%

• ort securit%

• =o7 classi$cation and marking and trustboundaries

• 3ddress Resolution rotocol 43R6 inspection

• >;3N 3ccess Control ;ist 4>3C;6• 7panning tree

• ower o#er &thernet 4o&6 and au!iliar% >;3Ns for

>oI(.(./.? Distribution ;a%er

The distribution la%er aggregates the data recei#ed fromthe access la%er switches before it is transmitted to the



core la%er for routing to its $nal destination. In the $gure"the distribution la%er is the boundar% between the ;a%er/ domains and the ;a%er ? routed network.

The distribution la%er de#ice is the focal point in thewiring closets. &ither a router or a multila%er switch isused to segment workgroups and isolate networkproblems in a campus en#ironment.3 distribution la%er switch ma% pro#ide upstream ser#icesfor man% access la%er switches.

The distribution la%er can pro#ide,

• 3ggregation of ;3N or +3N links

• olic%-based securit% in the form of accesscontrol lists 43C;s6 and $ltering

• Routing ser#ices between ;3Ns and >;3Ns andbetween routing domains 4e.g." &I@R to O726

• Redundanc% and load balancing

• 3 boundar% for route aggregation and

summarization con$gured on interfaces toward thecore la%er

• 8roadcast domain control" because routers ormultila%er switches do not forward broadcasts. Thede#ice acts as the demarcation point betweenbroadcast domains

(.(./.A The Core ;a%er

The core la%er is also referred to as the networkbackbone. The core la%er consists of high-speed networkde#ices such as the Cisco Catal%st B00 or B00. Theseare designed to switch packets as fast as possible andinterconnect multiple campus components" such asdistribution modules" ser#ice modules" the data center"and the +3N edge.3s shown in the $gure" the core la%er is critical forinterconnecti#it% between distribution la%er de#icesE fore!ample" interconnecting the distribution block to the+3N and Internet edge. The core should be highl%a#ailable and redundant. The core aggregates the tra9cfrom all the distribution la%er de#ices" so it must becapable of forwarding large amounts of data *uickl%.Considerations at the core later include,

• ro#iding high-speed switching 4i.e." fasttransport6

• ro#iding reliabilit% and fault tolerance

• 7caling b% using faster" and not more" e*uipment

• 3#oiding CU-intensi#e packet manipulationcaused b% securit%" inspection" *ualit% of ser#ice4=o76 classi$cation" or other processes

(.(./. Two-Tier Collapsed Core Design The three-tier hierarchical design ma!imizesperformance" network a#ailabilit%" and the abilit% to scalethe network design.

)owe#er" man% small enterprise networks do not growsigni$cantl% larger o#er time. Therefore" a two-tierhierarchical design where the core and distribution la%ersare collapsed into one la%er is often more practical. 3Fcollapsed coreG is when the distribution la%er and corela%er functions are implemented b% a single de#ice. Theprimar% moti#ation for the collapsed core design isreducing network cost" while maintaining most of thebene$ts of the three-tier hierarchical model.

The e!ample in the $gure has collapsed the distributionla%er and core la%er functionalit% into multila%er switch

de#ices. The hierarchical network model pro#ides a modularframework that allows e!ibilit% in network design andfacilitates ease of implementation and troubleshooting.

(./ Cisco &nterprise 3rchitecture

(./.( Hodular Network Design(./.(.( Hodular Design+hile the hierarchical network design works well withinthe campus infrastructure" networks ha#e e!pandedbe%ond these borders. 3s shown in the $gure" networksha#e become more sophisticated and comple!" withsome re*uiring connections to dedicated data centers"

often o'-site. 8ranch sites often re*uire connecti#it% tothe campus backbones" and emplo%ees wanted to beable to work from home o9ces or other remote locations.3s the comple!it% of the network increased to meet thesedemands" it became necessar% to ad:ust the networkdesign to one that uses a more modular approach.3 modular network design separates the network into#arious functional network modules" each targeting aspeci$c place or purpose in the network. The modulesrepresent areas that ha#e di'erent ph%sical or logicalconnecti#it%. The% designate where di'erent functionsoccur in the network. Using a modular approach hasse#eral bene$ts" including,

• 2ailures that occur within a module can be

isolated from the remainder of the network"pro#iding for simpler problem detection and highero#erall s%stem a#ailabilit%.

• Network changes" upgrades" or the introduction

of new ser#ices can be made in a controlled andstaged fashion" allowing greater e!ibilit% in themaintenance and operation of the campus network.

• +hen a speci$c module no longer has su9cientcapacit% or is missing a new function or ser#ice" itcan be updated or replaced b% another module thathas the same structural role in the o#erallhierarchical design.

• 7ecurit% can be implemented on a modular basisallowing for more granular securit% control.

The use of modules in network design enables e!ibilit%and facilitates implementation and troubleshooting.



(./.(.( Hodules in the &nterprise 3rchitecture3 modular approach to network design further di#ides thethree-la%er hierarchical design" b% pulling out speci$c

blocks or modular areas. These basic modules areconnected together #ia the core of the network.8asic network modules include,

• $ccess-distri#ution - 3lso called the

distribution block" this is the most familiar elementand fundamental component of a campus design.42igure (6.

• Ser%ices - This is a generic block used to identif%

ser#ices such as centralized ;ightweight 3ccessoint rotocol 4;+36 wireless controllers" uni$edcommunications ser#ices" polic% gatewa%s" andmore. 42igure /6.

• Data center - Originall% called the ser#er farm.

This block is responsible for managing and

maintaining man% data s%stems that are #ital tomodern business operations. &mplo%ees" partners"and customers rel% on data and resources in thedata center to e'ecti#el% create" collaborate" andinteract. 42igure ?6.

• &nterprise &dge - Consists of the Internet &dge

and the +3N &dge. These blocks o'er connecti#it%to #oice" #ideo" and data ser#ices outside theenterprise. 42igure A6.

(././ Cisco &nterprise 3rchitecture Hodel

(././.( Cisco &nterprise 3rchitecture

To accommodate the need for modularit% in networkdesign" Cisco de#eloped the Cisco &nterprise 3rchitecturemodel. This model pro#ides all the bene$ts of thehierarchical network design on the campus infrastructure"and facilitates the design of larger" more scalablenetworks.

The Cisco &nterprise 3rchitecture model separates theenterprise network into functional areas that are referredto as modules. The modularit% that is built into thearchitecture allows e!ibilit% in network design andfacilitates implementation and troubleshooting.

3s shown in the $gure" the following are the primar%Cisco &nterprise 3rchitecture modules,

• &nterprise Campus

• &nterprise &dge

• 7er#ice ro#ider &dgeConnected to the 7er#ice ro#ider &dge are additionalmodules including,

• &nterprise Data Center

• &nterprise 8ranch

• &nterprise Teleworker

(./././ Cisco &nterprise Campus3 campus network is a building or group of buildingsconnected into one enterprise network that consists ofman% ;3Ns. 3 campus is generall% limited to a $!edgeographic area" but it can span se#eral neighboringbuildings" for e!ample" an industrial comple! or businesspark en#ironment. Regional o9ces" 7O)Os" and mobile

workers ma% need to connect to the central campus fordata and information.

The enterprise campus module describes therecommended methods to create a scalable network"while addressing the needs of campus-st%le businessoperations. The architecture is modular and can easil%e!pand to include additional campus buildings or oorsas the enterprise grows.

The enterprise campus module consists of the followingsubmodules,

• 8uilding access

• 8uilding distribution

• Campus core

• Data center

Together these submodules,• ro#ide high a#ailabilit% through a resilient

hierarchical network design.

• Integrate I communications" mobilit%" andad#anced securit%.

• Utilize multicast tra9c and =o7 to optimizenetwork tra9c.



• ro#ide increased securit% and e!ibilit% usingaccess management" >;3Ns and I7ec >Ns.

The enterprise campus module architecture pro#ides theenterprise with high a#ailabilit% through a resilientmultila%er design" redundant hardware and softwarefeatures" and automatic procedures for recon$guringnetwork paths when failures occur. Integrated securit%protects against and mitigates the impact of worms"#iruses" and other attacks on the network" e#en at theswitch port le#el.3 high-capacit%" centralized data center module can

pro#ide internal ser#er resources to users. The datacenter module t%picall% also supports networkmanagement ser#ices for the enterprise" includingmonitoring" logging" troubleshooting" and other commonmanagement features from end to end. The data centersubmodule t%picall% contains internal email andcorporate ser#ers that pro#ide application" $le" print"email" and Domain Name 7%stem 4DN76 ser#ices tointernal users.(./././ Cisco &nterprise &dge

The enterprise edge module pro#ides connecti#it% for#oice" #ideo" and data ser#ices outside the enterprise.

This module often functions as a liaison between theenterprise campus module and the other modules.

The enterprise edge module consists of the followingsubmodules,

• &-commerce networks and ser%ers - The e-commerce submodule enables enterprises tosupport e-commerce applications through theInternet. It uses the high a#ailabilit% designs of thedata center module. De#ices located in the e-commerce submodule include web" application" anddatabase ser#ers" $rewall and $rewall routers" andnetwork intrusion pre#ention s%stems 4I76.

• 'nternet connecti%ity and demilitarized zone

(DM)* - The Internet submodule of the enterpriseedge pro#ides internal users with secureconnecti#it% to Internet ser#ices such as public

ser#ers" email" and DN7. Connecti#it% to one orse#eral Internet 7er#ice ro#iders 4I76 is alsopro#ided. Components of this submodule include$rewall and $rewall routers" Internet edge routers"2T and )TT ser#ers" 7HT rela% ser#ers" and DN7ser#ers.

• emote $ccess and +,N - The >N<remote

access submodule of the enterprise edge pro#idesremote-access termination ser#ices" includingauthentication for remote users and sites.Components of this submodule include $rewalls"dial-in access concentrators" Cisco 3dapti#e7ecurit% 3ppliances 43736" and network Intrusionre#ention 7%stem 4I76 appliances.

• $N - The +3N submodule uses #arious +3Ntechnologies for routing tra9c between remote sitesand the central site. &nterprise +3N links includetechnologies such as Hultiprotocol ;abel 7witching4H;76" Hetro &thernet" leased lines" 7%nchronousOptical Network 47ON&T6 and 7%nchronous Digital)ierarch% 47D)6" " 2rame Rela%" 3TH" cable"digital subscriber line 4D7;6" and wireless.

(./././ 7er#ice ro#ider &dge&nterprises use 7er#ice ro#iders 47s6 to link to othersites. 3s shown in 2igure (" the 7 edge module caninclude,

• Internet 7er#ice ro#iders 4I7s6

• +3N ser#ices such as 2rame Rela%" 3TH" and

H3N• ublic 7witched Telephone Network 47TN6

ser#ices The 7 edge pro#ides connecti#it% between theenterprise campus module to the remote enterprise datacenter" enterprise branch" and enterprise teleworkermodules.

The 7 edge module,

• 7pans across large geographic areas in a coste'ecti#e manner

• Con#erges #oice" #ideo" and data ser#ices o#er asingle I communications network

• 7upports =o7 and ser#ice le#el agreements

• 7upports securit% using >Ns 4Isec < H;76 o#er

;a%er / and ;a%er ? +3Ns+hen ac*uiring Internet ser#ices from an I7"redundanc% or failo#er should be considered. 3s shown in

2igure /" redundant connections to a single I7 caninclude,

• Single-homed - 3 single connection to an I7

• Dual-homed - Two or more connections to a

single I73lternati#el%" it is possible to set up redundanc% usingmultiple I7s" as shown in 2igure ?. Options forconnecting to multiple I7s include,

• Multihomed - Connections to two or more I7s

• Dual-multihomed - Hultiple connections to twoor more I7s

(././.? Remote 2unctional 3rea The remote functional area is responsible for remoteconnecti#it% options and includes se#eral modules,

&nterprise .ranch The enterprise branch module includes remote branchesthat allow emplo%ees to work at non-campus locations.

These locations are t%picall% responsible for pro#idingsecurit%" telephon%" and mobilit% options to emplo%ees"as well as general connecti#it% into the campus networkand the di'erent components located inside theenterprise campus. The enterprise branch module allowsenterprises to e!tend head-o9ce applications andser#ices" such as securit%" Cisco Uni$ed Communications"and ad#anced application performance" to the remotebranches. The edge de#ice connecting the remote site tothe central site #aries depending on the needs and sizeof the site. ;arge remote sites ma% use high-end Cisco

Catal%st switches" while smaller sites ma% use an I7R @/router. These remote sites rel% on the 7 edge to pro#ideser#ices and applications from the main site. In the $gurethe enterprise branch module connects to the enterprisecampus site primaril% using a +3N linkE howe#er" it alsohas an Internet link as a backup. The Internet link usessite-to-site Isec >N technolog% to encr%pt corporatedata.&nterprise /eleworker

The enterprise teleworker module is responsible forpro#iding connecti#it% for workers who operate out ofdi'erent geographicall% dispersed locations" includinghome o9ces" hotels or customer<client sites. Theteleworker module recommends that mobile users

connect to the Internet using the ser#ices of a local I7"such as cable modem or D7;. >N ser#ices can then beused to secure communications between the mobileworker and central campus. Integrated securit%- andidentit%-based networking ser#ices enable the enterpriseto e!tend campus securit% policies to the teleworker.7ta' can securel% log into the network o#er the >N andgain access to authorized applications and ser#ices froma single cost-e'ecti#e platform.&nterprise Data Center

The enterprise data center module is a data center withall of the same functional options as a campus datacenter" but e!ists at a remote location. This pro#ides anadded la%er of securit% as the o'site data center canpro#ide disaster reco#er% and business continuanceser#ices for the enterprise. )igh-end switches such as theCisco Ne!us series switch use fast +3N ser#ices such asHetro &thernet 4Hetro&6 to connect the enterprisecampus to the remote enterprise data center. Redundantdata centers pro#ide backup using s%nchronous andas%nchronous data and application replication.3dditionall%" the network and de#ices o'er ser#er and



application load balancing to ma!imize performance. Thissolution allows the enterprise to scale without ma:orchanges to the infrastructure.

(.? &#ol#ing Network 3rchitectures

(.?.( Cisco &nterprise 3rchitectures(.?.(.( IT Challenges

3s businesses ha#e grown more dependent on networks

for success" network architectures ha#e e#ol#ed o#er the%ears. Traditionall%" users" data" and applications werehoused on premise. Users could onl% access networkresources with compan%-owned computers. The networkhad distinct borders and access re*uirements.Haintaining securit%" producti#it%" and ser#ices wassimpler. Toda%" the network border has shifted" creatingnew challenges for IT departments. Networks aretransforming from a data-onl% transportation s%stem ofconnected ;3N de#ices" to a s%stem that enables theconnections of people" de#ices" and information in amedia rich" con#erged network en#ironment.3s new technologies and end user de#ices come tomarket" businesses and consumers must continue toad:ust to this e#er-changing en#ironment. There arese#eral new networking trends that continue to e'ectorganizations and consumers. 7ome of the top trendsinclude,

• 8ring our Own De#ice 48OD6

• Online collaboration

• >ideo communication

• Cloud computing These trends" while allowing for more ad#anced ser#icesthan e#er before" also introduce new securit% risks that ITmust address.

(.?.(./ &merging &nterprise 3rchitectures

The speed of change in market and businessen#ironments is re*uiring IT to be more strategic thane#er before. &#ol#ing business models are creatingcomple! technolog% challenges that IT must address.

To address these emerging network trends" new businessnetwork architectures are necessar%. These architecturesmust account for the network design principlesestablished in the Cisco &nterprise 3rchitecture" as wellas the o#erla%ing policies and technologies that alloworganizations to support emerging trends in a safe andmanageable wa%.

To meet this need" Cisco has introduced the followingthree network architectures" as shown in the $gure,

• Cisco 8orderless Network 3rchitecture

• Collaboration 3rchitecture

• Data Center<>irtualization 3rchitectureNote, Network architectures continuall% e#ol#e. Theintent of this section is to pro#ide an introduction ando#er#iew of emerging architecture trends.

(.?./ &merging Network 3rchitecture(.?./.( Cisco 8orderless Network

The Cisco 8orderless Network 3rchitecture is a networksolution that allows organizations and indi#iduals toconnect securel%" reliabl%" and seamlessl% to thecorporate network in a 8OD en#ironment. It is based onwired" wireless" routing" switching" securit%" and

application optimization de#ices working in harmon% tohelp IT balance demanding business challenges andchanging business models.It is not a static solution" but an e#ol#ing solution to helpIT e#ol#e its infrastructure to deli#er secure" reliable" andseamless user e!periences in a world with man% new andshifting borders.

It enables an IT department to architect and deplo% itss%stems and policies e9cientl% to all end user de#icesthat re*uire connection to the network. In doing this" itpro#ides secure" reliable" and seamless access toresources from multiple locations" from multiple de#ices"and to applications that can be located an%where.7peci$call%" the Cisco 8orderless network architecturedeli#ers two primar% sets of ser#ices,

• .orderless end-point0user ser%ices - 3sshown in 2igure (" 8orderless end-point < userser#ices connect the #arious de#ices to pro#ide

access to network ser#ices. De#ices that canconnect to the borderless network can range fromCs" to tablets and smart phones. It remo#es thelocation and de#ice borders" pro#iding uni$edaccess to wired and wireless de#ices. &ndpoint <user ser#ices de$ne the user e!perience and enablethe attributes of secure" reliable" and seamlessperformance on a broad range of de#ices anden#ironments" as shown in the $gure. 2or e!ample"most smart phones and tablets can download anduse the Cisco 3n%Connect software. It enables thede#ice to establish a secure" persistent" polic%-based connection for a seamless user e!perience.

• .orderless network ser%ices - 3s shown in

2igure /" 8orderless network ser#ices unif% theapproach to securel% deli#ering applications tousers in a highl% distributed en#ironment. Itsecurel% connects internal users and remote usersand pro#ides access to network resources. Thecrucial element to scaling secure access is a polic%-based architecture that allows IT to implementcentralized access controls.

The borderless network architecture supports a highl%secure" high-performing network that is accessible to awide range of de#ices. It needs to be e!ible enough toscale in its support for future growth in terms of businesse!pansion" including 8OD" mobilit% and cloud computingand must be able to support the growing re*uirements

for online #oice and #ideo.

(.?././ Collaboration 3rchitecture+orking in a collaborati#e en#ironment helps increaseproducti#it%. Collaboration and other t%pes of groupwareare used to bring people together for one reason oranother, such as to socialize" to work together" tocooperate and contribute to the production of something"and to inno#ate.

The Cisco Collaboration 3rchitecture comprises a portfolioof products" applications" software de#elopment kits47DJs6" and 3Is. The indi#idual components worktogether to pro#ide a comprehensi#e solution.

3s shown in the $gure" CiscoKs collaboration architectureis composed of three la%ers,

• $pplication and De%ices - This la%er containsuni$ed communications and conference applicationssuch as Cisco +eb&! Heetings" +eb&! 7ocial" Cisco

Labber" and Teleresence. The applications withinthis la%er help users sta% connected and producti#e.



These applications include #oice" #ideo" webconferencing" messaging" mobile applications" andenterprise social software.

• Colla#oration Ser%ices - This la%er supportscollaboration applications including the followingser#ices, presence" location" session management"contact management" client frameworks" tagging"and polic% and securit% management.

• Network and Computer 'nrastructure - This

la%er is responsible for allowing collaborationan%time" from an%where" on an% de#ice. It includes

#irtual machines" the network" and storage.(.?././ Data Center and >irtualization

The Cisco Data Center<>irtualization architecture is builtupon Cisco Data Center ?.0. It comprises acomprehensi#e set of #irtualization technologies andser#ices that bring the network" computing" storage" and#irtualization platforms together.

The data center architecture consists of threecomponents" as shown in 2igure (,

• Cisco 2ni3ed Management Solutions -Hanagement solutions simplif% and automate theprocess of deplo%ing IT infrastructure and ser#iceswith speed and enterprise reliabilit%. 7olutionsoperate transparentl% across ph%sical and #irtual

resources in cloud en#ironments.• 2ni3ed !a#ric Solutions - 2le!ible network

solutions deli#er network ser#ices to ser#ers"storage" and applications" pro#iding transparentcon#ergence" scalabilit%" and sophisticatedintelligence. 7olutions include Cisco Ne!us switches"Catal%st switches" Cisco 2abric Hanager" and CiscoNM-O7 software.

• 2ni3ed Computing Solutions - CiscoKs ne!t-

generation data center s%stem unites computing"network" storage access" and #irtualization into acohesi#e s%stem designed to reduce total cost ofownership 4TCO6 and increase business agilit%. TheCisco Uni$ed Computing 7%stem 4Cisco UC76 is built

with blade ser#ers" rack-mount ser#ers" fabricinterconnects" and #irtual interface cards 4>ICs6.

(.?./.? &!panding the Network These three architectures are built on an infrastructure of scalable and resilient hardware and software.Components of the architecture come together to buildnetwork s%stems that span an organization from networkaccess to the cloud" and pro#ide organizations with theser#ices the% need.

• 8uilding o' the basic network infrastructure"organizations can use these networkarchitectures to grow their network o#er time"adding features and functionalit% in an integratedsolution.

• One of the $rst steps in growing the network is

e!panding from the campus infrastructure to anetwork that connects remote sites through theInternet and through the +3N.

Documents

Cisco 4- Chapter 1