enhancing mpls

7/31/2019 Enhancing MPLS

1/14


2/14

Table of Contents

Enhancing MPLS Network Performance.........................................................................................3

Brief MPLS Review.........................................................................................................................3

Limitations and Solutions for Delivering QoS With MPLS ............................................................ 4

Challenge 1: Match the Right Traffic and Service Class ................................................................. 5

Precise Traffic Classification ................................................................................................... 6

Challenge 2: Prevent a Bottleneck ................................................................................................... 8

Challenge 3: Provide Performance Feedback .................................................................................. 9

Measuring Response Times....................................................................................................10

Access to MPLS Performance Data ....................................................................................... 11

Other Benefits of Using Packeteer in MPLS Networks.................................................................12

Preparing for MPLS ...............................................................................................................12Weighing the Cost of a Premium Class of Service ................................................................ 13

Marking, Pushing, Popping, and Swapping ........................................................................... 13

Delivering Network Backup...................................................................................................13

Assisting Voice/Data Network Convergence.........................................................................14

Summary ........................................................................................................................................ 14

Packeteer, Inc. 2


3/14

Enhancing MPLS Network PerformanceMulti-Protocol Label Switching (MPLS) is here to stay. Recent surveys indicate that the majority of large

organizations have either changed to MPLS-based IP VPNs (virtual private networks) or intend to change soon.

Most businesses make the move to take advantage of different classes of service to ensure appropriate application

performance.

Consider these perspectives:

MPLS is a fundamental protocol thats going to be used for the next ten to twenty years because its the first

complete and stable convergence protocol for data, voice, and video infrastructure.1

By 2007, IP VPN (frequently MPLS-based) will become the most popular WAN technology in the U.S.2

MPLS has become a leading vehicle for connecting an organizations distributed locations. It offers advantages to

both service providers and enterprises. For the service provider, MPLS reduces cost, simplifies provisioning,

provides wider service coverage, and enables differentiated services. In addition to the promise of multiple levels

of quality of service (QoS), MPLS offers the enterprise a meshed architecture, scalability, and network

convergence, eliminating the need for multiple networks.

Service providers need to make their bandwidth services more valuable to enterprises. After all, pitching

bandwidth as a stand-alone commodity is no longer compelling. One opportunity for service expansion isdifferentiated performance standards. Meanwhile, enterprises realize the importance of ensuring that key business

applications operate consistently, reliably, and promptly requirements that become essential as organizations

adopt converged networks supporting voice, video, and data. Based on these advantages, its no wonder that

MPLS, with its ability to offer different performance levels to different applications, seems to be the ideal solution

for both parties.

On paper, it all makes sense. However, once MPLS is implemented, organizations frequently discover that

placing key applications into premium service classes does not reap the expected benefits. What goes wrong?

Bandwidth contention within service classes, overloaded premium classes, bottlenecks outside the MPLS

cloud they all can result in poor and unpredictable application performance. Furthermore, the complex

requirement of mapping large numbers of applications (often numbering in the hundreds) to a relatively small

number of MPLS classes creates confusion, and it leaves businesses with unfulfilled performance and cost-benefitexpectations.

Packeteer, the leading provider of application traffic management solutions, offers an integrated platform that

addresses the obstacles associated with MPLS networks. Packeteer boosts application performance, manages the

complexities of juggling each service class traffic load, eases bandwidth bottlenecks, and verifies application and

service-level performance, providing a very cost-effective complement to MPLS.

This paper details the obstacles that emerge in MPLS environments and the value Packeteer brings to application

performance as it solves these operational issues.

Brief MPLS ReviewAs a brief reminder of how MPLS operates, recall that in the typical network without MPLS, packet paths are

determined in real time as routers decide each packets appropriate next hop. Conventional IP routing requires

time and eliminates opportunity to influence packets paths. With MPLS, explicit and pre-defined network paths

transport specific types of traffic.

1 Hossein Eslambolchi, CTO and CIO of AT&T; President of AT&T-Labs; from Point of View/Networking and Business

Strategy, 06/03/2003.2 IDC, U.S. IP VPN Services Forecast, 2002-2007 (IDC # 28575).

Packeteer, Inc. 3


4/14

MPLS solved the problem that router manufacturers faced when incorporating QoS into very large IP-VPN

networks: ensuring that each and every router can identify and process each and every traffic flow appropriately

requires so much processing power as to be ineffective and non-scaleable.

A better approach, and the one that MPLS adopts, is to label traffic flows at the edge of the network and let core

routers identify the required class of service with a simple and quick label check. MPLS reduces the burden of

differentiating types of traffic and assigning appropriate class-of-service labels by focusing the task on the edge of

the MPLS network. The onus is usually on a router, called the label edge router, or LER.

Optimally, the MPLS labels indicating the best and fastest service classes go into the most urgent applications

packets (and only the most urgent applications packets).

Limitations and Solutions for Delivering QoS With MPLSThe ability to provide diverse applications with appropriate bandwidth and performance is part of MPLS purpose

and design. So, why do organizations frequently find it difficult to realize the benefits of MPLS?

Service providers do an excellent job of providing an MPLS core network with different service classes.

However, an MPLS solution degrades as it faces three major challenges:

Challenge 1: The right traffic does not get placed in the right MPLS service class. Premium classes deliversub-premium performance as they drown in copious non-urgent traffic; important applications are improperly

assigned to only best-effort classes.

Challenge 2: Traffic gets hung up in a congested bottleneck just before each entry point to the providers

MPLS network. In addition, unmanaged traffic heading into a LAN (inbound) grows unruly, using an

inappropriately high flow rate.

Challenge 3: Providers and enterprises need information on the performance of each application and each

service class transported over their

MPLS network. Concrete, quantified

service-level assessments are rare.

MPLS and Packeteerimprove responsetimes.

Packeteer complements MPLS

installations and overcomes each of thethree QoS challenges listed above with

pragmatic, real-world solutions. Packeteer

offers visibility into and control of

application traffic and enhances MPLS

performance gains as it:

Detects, identifies, and classifies

diverse applications, assigning distinct

QoS tags

Packeteer, Inc. 4


5/14

Ensures that the traffic within a particular MPLS service class is the right traffic, meant for that class

Eases the bottlenecks that form at the entry points to MPLS networks

Extends MPLS performance benefits to the network edge and users premises

Measures and graphs per-application and per-MPLS-class performance, enabling assessment of service level

agreement (SLA) compliance

Unlike other elements of the MPLS network, the enterprise typically owns and manages Packeteer products. Aservice provider can also use Packeteer to offer customers additional services. Packeteer appliances are deployed

at the network edge just before each locations entry point to the MPLS network.

Packeteer appliances sit on the LANimmediately before the serviceproviders routers leading into and outof the MPLS network.

Challenge 1: Match the Right Traffic and Service ClassThe ability to match an application to an MPLS class of service is a prerequisite for an effective QoS

implementation. After all, if network equipment is unable to identify which application is passing, how can it

determine the appropriate service level? With the most granular and specific application classification, comes the

most accurate and beneficial MPLS service-class assignments. If it is not possible to identify applications, it is

also not possible to ensure that a particular application gets its proper MPLS label and corresponding class ofservice.

Precise application classification requires the ability to analyze traffic flows at all networking layers including the

application layer, layer 7. Traffic classification must find and decipher application-specific information contained

within transported data.

If MPLS solutions depend only on layer-4 port numbers to identify applications, not only do non-critical (or

recreational) applications pass undetected, but they also seize bandwidth from premium (and more costly) MPLS

classes. These questions highlight examples:

Some ERP applications use any one of 10,000 layer-4 port numbers. Which ERP traffic actually gets

identified as ERP? All? Some? None?

Some recreational traffic searches for open ports on firewalls, disguising itself as ERP or HTTP. Will KaZaAget a class of service that is appropriate for recreational traffic? Or will it get ERPs service class?

Because the routers at the edge of the MPLS network use port numbers to identify traffic, most service providers

require organizations to manually map each TCP port number and IP address to each application and user, and

then in turn to a provisioned MPLS class.

Even if a business doesnt mind tending to this manual-mapping task, another fundamental problem remains.

Once traffic is assigned to an MPLS class, any single flow can consume the class entire bandwidth. One high-

capacity user or one flow from an unsanctioned bandwidth-hungry application can undermine performance of

ERP or other mission-critical applications.

Packeteer, Inc. 5


6/14

Without tools to differentiate and analyze each application, the premium MPLS class traffic can appear to be in

compliance with the providers service level agreement. However, behind the scenes, rogue traffic might be the

only beneficiary of costly premium performance.

Label edge routers application classification capabilities are limited. They lack precision and accuracy when

tagging or labeling MPLS traffic. This is the core problem behind the discrepancy in organizations expected and

actual application performance.

Application7

6 Presentation Packeteer classifies traffic using application-specificinformation contained within the data and at all layersthrough layer 7.

5 Session

4 TransportThis traffic tree organizestraffic first by class-of-service and then by

application. Users cancontrol bandwidth andexamine performance fortraffic in any branch of thetree no matter howgranular its classification.

3 Routers classify traffic by IP address or TCP portnumber, but many applications share the same TCPnumber, and IP addresses are assigned dynamically.

Network

2 Data Link

1 Physical

Precise Traffic Classification

The ability to distinguish one type of traffic from another as it passes from a

non-MPLS edge to an MPLS core is essential to ensure that applications areassigned to the correct class of service. Only with precise classification can

applications be treated according to their respective business importance.

Many products can differentiate traffic based on MAC, IP address, and portnumbers, and then perhaps infer an application using a static port number. A

few vendors offer limited application-layer classification for specific traffic

types over specific ports. Packeteer offers all these same address- and port-

based techniques, but goes far beyond them to identify an incredible diversity

of complex applications. Packeteer scrutinizes multiple packets in a flow,

behavioral characteristics, application markers, and traffic histories to

determine precisely which applications are in use.

Packeteers classification feature builds a hierarchical classification tree,

inserting an entry for every distinct traffic type it identifies. A traffic tree

provides an organized view of a traffic mix and makes it easy to assign

bandwidth-allocation or QoS-tagging policies to entire traffic categories withone step.

Packeteer, Inc. 6


7/14

Some of the applications and protocols Packeteer automatically detects, identifies, and classifies include:

Client/ServerCVSFIX (Finance)Folding@HomeINFOC-RTMSINT-1 (Unisys Interact)MATIP (Airline)MeetingMaker

NetIQ AppMngrOpenConnect JCPPEPGate (Attachmate)Unisys-TCPA

Content DeliveryArielBackwebChaincastEntryPointKontikiMarimbaNewsStandPointCastWebShots

Database and ERPBaanFileMaker Pro

JDENet (JD Edwards)MS SQLOracle (and by database)Oracle JVMOracle EMPostgreSQLProgressSAP

Directory ServicesCRSDHCPDNSDPAFingerIdentKerberosLDAPRADIUS

RRPSSDPTACACSwhoisWINS

E-mail andCollaborationBiffccMAILDCOM (MsExchange)Groupwise (Novell)IMAPLotusNotesMSSQOSIPOP3SMTP

File ServerAFSCIFS-TCPCU-DevlockdMicrosoft-dsNetBIOS-IPNFS

Novell NetWare5rsyncSunND

GamesAsherons CallBattle.netDiablo IIDoomEverQuestHalf-LifeKaliLucasArts (Jedi*)MSN ZoneMythicQuake I, II, & IIISonyOnlineTribes I,IIUnreal

Warcraft IIIYahoo! Games

HealthcareDICOMHL7

Host AccessATSTCPAttachmatePersoft PersonaSHARESUDPSMTBFTN3270TN5250

InternetActiveXBITS

FTP, Passive FTPGopherHTTPHTTP TunnelIP, IPv6, IPIP, UDP,TCPIRCMime typeNNTPSocks2httpSSHTCPSSLTFTPUUCPURLWeb browser type

Legacy LANand Non-IPAFPAppleTalkDECnetFNA, FNAonTCPIPXLAT

MOP-DL/RCNetBEUIPPPoESLPSNA

MessagingAOL IM,

Talk, Image,File, ISP,

ICQIRCLotus IMMSN MessengerWindows-POPUPYahoo! Messenger

MiddleWareCORBAJava RMI

SmartSocketsSunRPC (dyn port)JavaClient

MultiMediaMPEG (Audio, Video)Multi-cast NetShowNetMeetingQuickTimeRadio@NetscapeReal (Audio, Video)RTPRTSPSHOUTcastStreamworksVideoFrameWebExWinampStreamWinMedia

Music P2PAimsterApple-iTunesAudioGalaxy

RhapsodyMac Satellite

Bit TorrentBlubster

DirectConnectEDonkeyEmuleOvernet

FileRogueFiletopiaFurthurnetGnutella

AcquisitionAresBearShareFuriGnotellaGnucleusgtk-gnutellaLimeWireMyNapsterMactellaMorpheusMutellaNap Share

PhexQtraxmaxQtellaShareazatoadnodeXoloX

GrooveHotlineiMeshKaZaAKaZaA LiteNapster

AmsteraudioGnomeFile NavigatorGnapsterGrokstergtk napsterjnapsterMacStarMaxter

My NapsterNapigatorNapMXNapster Fast SearchNapster, MacOSXOpenNapRapsterSnapSpotlightWebNapWinMX

Napster2PeerEnablerScourTripnosisWinny

NetworkManagementCisco DiscoveryDay-TimeICMP(by packet type)IPCompMicrosoft SMSNTP

RSVPSMSSNMPSYSLOGTime Server

PrintIPPLPRTN3287TN5250p

RoutingAURPBGPCBTDRPEGPEIGRP

IGMPIGPMPLS (+tag, +app)OSPFPIMRARPRIPSpanning TreeVLAN (802.1p/q)

SecurityProtocolDLSDPAGREIPMobilityIPSECISAKMP/IKE keyexch

L2TPPPTPRC5DESSOCKS ProxySSHSSL (+shell)swIPe

SessionGoToMyPCpcAnywhereREXECradminrloginrshTelnet

TimbuktuVNCXwindows

Thin Client orServer BasedCitrix

Published Apps,Nfuse, IMA

RDP/Terminal Server

Voice over IPCiscoCTIClarentCUSeeMeDialpadH.323I-PhoneMCK Commun.

MegacoMicom VIPMGCPNet2PhoneRTPRTCPSIPSkinny (SCCP)T.120VDOPhone

Packeteer can classify traffic by a wide range of variables, including the following:

Advanced Layer 7 application signatures

Application sub-classification including Oracle and PostgreSQL (by database), Citrix (by published

application or priority tag), FTP (by file name or extension), NNTP (by name or type of newsgroup), VoIP

(by protocol or CODECs)

HTTP sub-classification by URL, URL wildcard, content type, MIME type, browser type, HTTP tunnel,

HTTP 1.1 virtual server

SSL sub-classification by certificate common name

Packeteer, Inc. 7


8/14

Layer 4 UDP and TCP ports, port ranges, and port lists

Layer 3 IP addresses, address ranges, subnets, subnet ranges, MAC addresses, host lists, and LANs or

physical device

QoS markings, including DiffServ, IP-ToS, IP-CoS, IP precedence, MPLS label, MPLS experimental bits

Frame relay interface, PVC/DLCI, ATM PVC, ATM interface, ISL-VLAN, 802.1q-VLAN, 802.1p-LAN

Once Packeteer identifies each passing packet, it can tag each packet with a DiffServ or IP TOS (type of service)identifier to give LERs the criteria they need to assign proper MPLS labels. As Packeteer identifies, differentiates,

and tags applications, it ensures that only appropriate applications are assigned to any MPLS service class. It

eliminates the contention issue that happens when too many applications go into the same service class because of

a lack of visibility into various types of traffic. The frequency of missed SLAs declines.

For example, with Packeteer, SAP and Oracle traffic can share one service class or have two distinct classes.

Either way, they can sit in a separate MPLS service class than the best-effort class used for email and downloads.

In another example, Citrix Published Applications and NFuse (using the ever-popular port 80) can have a higher

service class than that assigned to web surfing and file sharing, also on port 80.

Typically, the enterprise does not get involved with MPLS labels, leaving all MPLS involvement (including

labels) to the service provider. However, Packeteer does have the ability to tag packets directly with MPLS labels

if the enterprise or service provider wishes to do so.

Challenge 2: Prevent a BottleneckThe transition from a non-MPLS edge to an MPLS core or WAN typically turns into a speed-conversion

bottleneck as traffic from a speedy Ethernet LAN funnels into a slower line. Critical traffic at this bottleneck is

not yet the beneficiary of MPLS performance advantages, as the traffic is not yet within the MPLS network

cloud.

MPLS implementations are usually done in the network core, leaving local LANs at the network edge as they are.

Simply deploying an MPLS core network to deliver QoS wont yield end-to-endQoS for applications. The link

from the local LAN to the MPLS core is typically the lowest capacity portion of the network. It backs up with

deep queues and introduces the most latency. Even if SAP, for example, has been assigned to the premium class

within the MPLS network, it might wait behind FTP packets and web traffic before entering.

Packeteer eases the bottleneck, ensures that key business applications can always access the network, and

eliminates or reduces queuing within LERs, a main contributor to unpredictable traffic delay. As Packeteer detects

and identifies each application or traffic type needing assignment to a particular service class, it can also

determine how that traffic should pass through the bottleneck point.

Packeteer also regulates the rate at which traffic enters the network on the other side of

connections, making sure that inbound traffic doesnt grow unruly and exceed its

expected flow rates.

Its as if each application ortype of traffic gets its ownappropriately sized link.

If an application doesntneed its bandwidth at themoment, it goes to another

that does. Bandwidth isnever wasted.

Policy-based bandwidth allocation boosts or curbs application performance over

the WAN or Internet. Packeteers flexible policies protect

critical applications, pace greedy traffic, limit recreational

usage, and block malicious traffic. Bandwidth minimums

and/or maximums apply to each application, MPLS class of

service, session, user, and/or location. Each type of traffic

maps to a specific bandwidth-allocation policy, ensuring that

each receives an appropriate slice of bandwidth.

An MPLS class of service is based upon a given traffic load.

If the load grows too large, the MPLS implementation can

drop excess traffic into a lower class of service. The portion of traffic that gets demoted is not necessarily the

applications that someone would choose for slower service. Packeteer can ensure that the amount of traffic

Packeteer, Inc. 8


9/14

entering an MPLS class does not exceed the expected and predefined volume for that class, preventing

unexpected drops in service.

With Packeteer, organizations can:

Protect the performance of important applications, such as SAP and Oracle, or all applications in a premium

MPLS class of service

Enforce limits on traffic volume in each MPLS class of service

Provision steady streams for voice or video traffic to ensure smooth performance

Stop applications or users from monopolizing the link

Contain unsanctioned and recreational traffic such as KaZaA and AudioGalaxy

Reserve or cap bandwidth using an explicit rate, percentage of capacity, or priority

Strike a balance between consistent access and a bandwidth limit for applications such as Microsoft Exchange

that are both bandwidth-hungry and critically important

Allow immediate passage for small, delay-sensitive traffic such as Telnet

With Packeteers control features, performance matches application characteristics, business requirements, and

user needs.

These graphs compare usage andefficiency, before and after usingPacketeers control features.

Bandwidth usage smoothes outand avoids spiky peaks andvalleys that create inconsistentdelays.

Retransmissions and their wastedbandwidth are all but eliminated.

Challenge 3: Provide Performance FeedbackWhen a service provider and enterprise enter into a contract for an MPLS network, they must agree on their

service classes. For example, there might be four classes of service: Voice (for VoIP calls), Gold (for urgent

business-critical applications), Silver (for important but less urgent applications), and Bronze (for traffic requiring

only best-effort performance with leftover resources). Each class of service maps to performance commitments,

an SLA.

How do providers and enterprises validate that results match expectations? Can sub-par performance be attributed

to the provider or enterprises network? Clear answers can help prevent conflicts and wasted diagnostic time.

Packeteer, Inc. 9


10/14

Both providers and enterprises need precise performance measurements for flexible intervals of time. Both parties

also need to be able to divide delay measurements between the provider and enterprises area of responsibility.

Traditional methods for measuring MPLS SLAs provide information only on the performance of a service class

aggregate traffic. Enterprises enter a contract for delay, availability, throughput, and/or other metrics, based on

averages in each service class.

If one particular application in

the MPLS class suffers poor

performance, it is quite possible

that the overall SLA for the

class would remain compliant.

It is important for any

organization that uses MPLS for

application QoS to be able to

measure all metrics for a single

specific application. In addition,

when auditing SLA compliance,

averages based on long sample

periods are of less value than

exact information based oninstantaneous peaks and short-term averages.

Packeteers comprehensive reports provide a clear view of historical performance, load, and efficiency. Extensive

measurement data lives on board for up to two months and forms the foundation for Packeteers reports, all

accessible with a web browser. More than 100 types of metrics are available for export and incorporation into

third-party reporting tools. In addition, Packeteer ReportCenter can centralize reporting functions for multiple

Packeteer appliances at edge locations (all the MPLS network entry points at branch offices, for example).

ReportCenter can render many additional predefined reports and store measurement data for long periods of time.

Measuring Response Times

Packeteers position in the network monitoring all traffic that passes gives it a unique opportunity to

provide accurate response-time measurements at a very low cost. Because it already sees every packet, Packeteercan calculate the time traffic spends traveling between a client and a server, the time used by the server, and the

time spent on either side of a Packeteer appliance. Rather than collecting response data, Packeteer notes response

times as traffic passes. This simple approach provides rich data without network impact or overhead.

Packeteers response-time management facility offers techniques to measure performance, troubleshoot sluggish

response, set service-level goals, and assess compliance. Organizations can:

Track delay statistics for flexible traffic categories. Measure response times for an MPLS service class,

individual application, host, subnet, and any transaction-oriented TCP traffic.

Split each response-time measurement into network delay (time spent in transit) and server delay (time the

server used to process the request).

Identify users and servers with the slowest performance.

Set acceptability standards and track whether performance adheres to them. Set the speed that divides goodresponses from bad (500 ms for the Gold MPLS class of service, for example), and set the percentage of

transactions that should meet designated performance goals (95 percent, for example).

Split network delays into time spent on either side of a Packeteer appliance. When Packeteer sits at the

boundary between the enterprise and providers networks, separate metrics provide a clear, unambiguous

dividing line of responsibilities. When performance is slow, these metrics indicate on which side of the

dividing line the slowdown occurs.

Packeteer, Inc. 10


11/14

View current and historical performance data in intuitive tables and graphs, in a MIB (management

information base) via an XML API or as raw data. SNMP management tools and third-party reporting tools

integrate smoothly.

With a mechanism to compare actual and anticipated performance on an MPLS network, service-level agreements

become more than empty promises.

See total transaction times dividedinto their network and servercomponents.

This graph shows that response timehas been sporadically slow withfrequent spikes. In addition, it showsthat it was not the server that wascausing the problems it was thenetwork.

If this is a graph of a criticalapplication, its performance definitelyneeds some help. Some ofPacketeers control features andperhaps a different MPLS serviceclass are in order.

Access to MPLS Performance Data

If an enterprise owns and manages its own Packeteer appliances, then it can access any of the relevant reports to

verify or diagnose performance. But if the service provider owns and manages Packeteer appliances, then the

provider must find a convenient way to convey performance information to customers. The most convenient way

to convey information is through a web page. But the repetitive, manual chores required to continually publish up-

to-date reports are painful.

Packeteers customer portal is a web page that serves as a vehicle for delivering information about MPLS network

usage, performance, and status to a customer. Per-customer tailored web pages offer information for any

application or MPLS class of service, including average and peak bandwidth rates, response times, and efficiency.

Customers can check their own status, thereby reducing the volume of support calls. Trust increases as all partiesaccurately monitor factors such as availability, usage, and performance.

Reports are presented in HTML pages that the provider designs, using templates provided at the Packeteer

website. The provider chooses either a single HTML page with customized data or a separate HTML page for

each customer. Packeteer maintains the portals HTML pages, automatically customizes them for each viewer,

serves the HTML pages when requested, and insulates customers from each others data.

The customer portal offers the ability to:

Generate metrics, graphs, tables, and reports that describe and validate usage and performance

Brand the look and feel of the web page for each customer or group

Notify customers of service changes or other timely messages

Ensure customers are informed with no need for help-desk support

Packeteer, Inc. 11


12/14

Example of acustomer portal

Other Benefits of Using Packeteer in MPLS NetworksEarlier sections of this paper covered the three most significant benefits of deploying Packeteer in an MPLS

network: (1) getting the right traffic on the right MPLS path; (2) avoiding a congested bottleneck at each MPLS

entry point; (3) assessing MPLS service-level performance. Additional benefits are also available.

Preparing for MPLS

Before implementing an MPLS network, organizations typically confront a few challenges during planning

stages. Issues that Packeteer can determine or address include:

Application mix

Before determining MPLS service classes, its important to know the applications that are running over the

network. As soon as Packeteer initiates automatic application discovery, organizations are often surprised by

some of the types of traffic that appear in their traffic trees.

Packeteer, Inc. 12


13/14

Load

Organizations are often confounded when trying to select the sizes for each of their MPLS service classes.

How big should the most premium class be? How about the best-effort class that will support all leftover

traffic? Packeteer automatically measures load for each traffic category as it passes. If the organization

classifies its auto-discovered traffic types into categories for each intended MPLS service class, then it can see

each MPLS class load even before the MPLS network exists.

Pre-MPLS baseline picture

MPLS networks should improve the consistency and speed of critical applications performance. But

improvements are difficult to verify without a basis of comparison a performance before picture.

Packeteer can measure application performance before and after MPLS deployment. Packeteer recommends

three performance snapshots one before MPLS and traffic managements control features are applied; one

before MPLS and after control features are applied; and one after both. These three snapshots provide a

complete picture.

Weighing the Cost of a Premium Class of Service

Once an organization deploys an MPLS network, it pays a different rate for each MPLS service class.

Presumably, a Platinum class costs more than Gold, which costs more than Silver, which costs more than Bronze,

and so on.

With Packeteer, the enterprise can compare performance in two MPLS service classes to determine if a cost

premium is worth it. For example, it could compare average response times for Gold and Silver service classes

traffic, revealing whether the difference in performance merits the difference in cost.

A service provider could also do the same comparison using Packeteer. If the comparison reveals a less-than-

anticipated performance difference, the provider might consider some performance tuning on the premium class.

If its greater than anticipated, the provider might decide to raise its premium rates in the future.

Marking, Pushing, Popping, and Swapping

Most Packeteer-MPLS implementations entail marking traffic with DiffServ or IP TOS tags to relay class-of-

service intentions to the LER, which does the actual MPLS labeling. However, Packeteer can also tend to MPLS

labels itself, if desired.

One packet can have more than one MPLS label in its header. All labels reside in the packets MPLSstack, an

ordered list of labels that is processed on a last-assigned/first-removed basis. Routers frequently assign (called

push), remove (calledpop), or exchange (calledswap) labels in each packets MPLS stack as they route.

Packeteer can also perform these three operations push, pop, and swap as packets pass, relieving routers of

extra overhead.

Delivering Network Backup

Organizations commonly consider MPLS networks when deploying

new, business-critical applications such as VoIP or ERP. However,

should the MPLS network fail, an alternate connection is needed.

Typically, a back-up connection has less capacity than the primary

connection. If and when the secondary connection becomes active,

application contention becomes a more significant problem as key

applications fail or are so slow as to be unusable.

Packeteer can control traffic over slower back-up networks to

ensure that key applications remain usable, even in the case of a

major network failure. With multiple physical interfaces, Packeteer

can implement different traffic management strategies for the

primary and back-up connections. Each interface can have its own

Packeteer, Inc. 13


14/14

settings for bandwidth-allocation policies, application priorities, and traffic marking. Although intervals of normal

usage on the primary network might feature a mix of applications with network access, back-up mode might

permit network access only to critical applications and save non-critical applications until spare bandwidth is

available. Many other strategies are possible.

Assisting Voice/Data Network Convergence

For many, planning a VoIP installation is the catalyst for considering an MPLS network. A network that supportsboth voice and data needs multiple QoS levels, and thats precisely what brings MPLS to mind.

Packeteer facilitates network convergence, again complementing the advantages that MPLS offers. In preparing

for a VoIP installation, Packeteer helps organizations:

Determine how much bandwidth voice traffic will need.

Simulate peak call volumes impact on existing applications and their performance.

Decide if a capacity upgrade is needed.

Once VoIP and data are both active on one network, Packeteer can:

Identify many types of voice traffic, including RTCP, SIP, Megaco, MGCP, Skinny, MCK-Signaling, RTP,

MiCOM VIP, MCK Voice, and others.

Protect bandwidth for VoIP as a whole.

Clear easy passage for VoIPs setup and control traffic.

Allocate the steady rate required for good performance for each voice stream.

Handle over-subscription (every employee suddenly decides to use the phone at the same time) gracefully.

Assign appropriate QoS tags or MPLS labels.

Control bandwidth allocation appropriately for competing data applications.

SummaryAs a growing number of organizations turn to MPLS networks for network convergence and a range of service

levels, the need for assistance in MPLS preparation and delivery ofend-to-endquality of service becomes more

significant. Packeteer provides that assistance.

Incorporating Packeteer in MPLS networks from planning through management offers compelling

advantages. It helps determine what to purchase; identifies and marks the application traffic needing special

handling; assesses performance; and keeps traffic sailing smoothly at the entry and exit points of an MPLS

network, extending the performance advantages of an MPLS core network all the way to the edge.

With Packeteer, network and application performance align with business needs.

If youd like more information about Packeteer solutions, consult Packeteers web site or call 408-873-4400 or

800-697-2253.

Packeteer, Inc. 14

enhancing mpls

Documents