QoS in IP Networks: an industrial viewpoint International Workshop on: “QoS in Multiservice IP Networks” Rome, 24-26 January 2001 Sergio R. Treves Alcatel
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Q oS in IP N etw orks:an industria l v iew point
In ternationa l W orkshop on:“Q oS in M ultiserv ice IP N etw orks”
Rom e, 24-26 January 2001
Serg io R . Treves
A lcate l
S . Treves
Sum m ary
▼ N etw ork m ode l
▼ Param eters and requ irem ents fo r Q oS
▼ R eference netw ork con figura tions fo r End-to -End Q oS
▼ M ain Q oS techn iques and netw ork arch itectu res
▼ C onclus ions
-1-
S . Treves
N etw ork M odelN etw ork M odel
-2 -
S . Treves
N et-Econom y B usiness m odel
InternetService
Prov iders
(IS Ps)
A pplicationS erv ice
P rov iders (A S P s)
Retail
C onsum er
En terprise
C ost / Bandw id thVa lue AddedApp lica tions
M u ltiM ed iaB roadbandQ oS
M obileS erv iceP rov iders(M S P s)
G S MG P R S
U M TSE D G E
C om petitiveA ccessP rov iders(C A P s)
C ab le
LM D SP O N
W D M
S atelliteA D S LV D S L
B ackbone S erv iceP rov iders (B S Ps)
IP / M P LSD W D M
S oH o
S M E
C orpora te
C PEC PE A ccess E dgeA ccess E dge C oreC ore
Wholesale WholesaleRetail
E stab lished Serv iceP rov iders (ES P s)TD M
N B W ire linexD S L
-3 -
S . Treves
N ext G eneration N etw ork m odel
NetworkIndependent
Services
Call Server
Services
Sign. Gway
Gateways
Legacy NetworkM edia
Legacy NetworkS igna lling/Service
-4-
S . Treves
C om m unication Scenarios
▼ PC to PC▼ PC to G atew ay
PSTN
PSTN IP
▼ G atew ay to G atew ay
-5-
S . Treves
Param eters and R equirem entsParam eters and R equirem entsfor Q oSfor Q oS
-6 -
S . Treves
Q uality of Serv ice (Q oS)
▼ Q uanta tive m easure of the degree of satis faction perce ived byan end user (custom er) o f a serv ice, expressed by m eans ofQ oS param eters that can be m easured inc lud ing:
◗ ava ilab ility◗ erro r perfo rm ance◗ response tim e◗ los t ca lls due to netw ork congestion
▼ Serv ice P rov ide rs m ay guaran tee a particu la r leve l o f Q oS tothe ir custom ers by m eans o f a Serv ice Leve l Agreem ent (SLA)
-7-
S . Treves
Q uality of Serv ice A spects
▼ N etw ork Perform anceaspect
▼ End-U ser aspect
❑ Tra ffic pe rfo rm ance: th roughtpu t, de lay& jitte r, loss
❑ E rror perfo rm ance❑ D ependab ility : ava ilab ility , re liab ility ,
m a in ta inab ility
❑ S ervice re ta inab ility (p rovis ion for arequested du ra tion)
❑ S ervice in teg rity (p rov is ion w ithout excess iveim pa irm en ts)
❑ S ervice accessib ility (w hen requested)
-8-
S . Treves
Layer-specific Q oS for Vo ice
App lica tion layer
Te lephony se rv ice = tw o-w ay
transport o f vo ice signa ls a t a deside red qua lity R
T ransport se rv ice = one-w ay
transport o f vo ice packe ts
Encod ingFECPacke tiza tion
D ejitte ringD ecod ing
IP N etw ork layer
E gresspo in t
Ing resspo in t
-9 -
S . Treves
R elevant Q oS Param eters
▼ IP N etw orkIP N etw orkLayerLayer
▼▼ A pp lica tionA pp lica tionLayerLayer
• Ingress-to -Egress delay
• Ingress-to -Egress jitter
• Ingress-to -Egress packet loss
• M outh-to -Ear de lay
• D istorsion of the vo ice s igna l
- encod ing /decod ing- packetisa tion de lay- de jitte ring loss
due to:
-10 -
S . Treves
U M TS Q oS C lassesdefined by 3G PP (standards TS 23 .107)
Real-T im eConversationa l
Rea l-T im eStream ing
Non Real-T im eIn teractive
Non Real-T im eBackground
stringen t
constra ined
no
no
stringen t
constra ined
no
no
no
no
yes
yes
Y es(C B R , V B R )
Y es(V B R )
N o(V B R )
N o(A B R )
Transfer
D elay
requirem ent
Transfer
D elay
V aria tion(J itte r)
Low b it
erro r rate
G uaran teed
bit rate
Typical
applications
V oIP , V ideo-conferenc ingA ud io-conferenc ing
B roadcast se rv ices(aud io , v ideo), N ew s, S ports
W E B brow sing, In teractiveC ha t, G am es, m -com m erce
E -m ail, S M S , databasedow nloads
C haracteristics
Traffic type
-11 -
S . Treves
Q oS C lasses defined by ETSI T IPH O N
C lass C lass 4: Best(bette r than toady’s
P S TN /IS D N )
O vera ll SpeechTransm ission Q ualityRating (R ) G .109
90≤R<100
C lass 3: H igh(equ iva lent to today’s
P S TN /IS D N )
C lass 2: M ed ium(equ iva lent to today’s
w ire less netw o rks)
C lass 1: Low(s ign ificantly im pa ired,
bu t usab le)Param eter
End-to-End Delay(m s)
< 100
L isten ingSpeech Q uality(one way, nonconversationa l)
Bette r thanG .711
Equiva lent orbette r thanG .726 at 32 kb/s
Equ iva lent orbette r thanG SM -FR
Undefined
80≤R<90 70≤R<80 60≤R<70
< 100 < 150 < 400
TIP H O N = Te lecom m unica tion Internet P ro toco l H a rm onization O ver N etw o rks
-12 -
S . Treves
R eference N etw ork C onfigurationsR eference N etw ork C onfigurationsfor E2E Q oSfor E2E Q oS
-13 -
S . Treves
C urren t G eneration N etw ork
N etw orkP ee ring
E S P /M S PC A P /IS P
vo iceda ta
POTSBA, PRA
ADSLHFC
POTSBA, PRA
da ta
C orpora te and R esidentia l C P E
IS P /IA P
‘In ternet Backbone’and other ‘Carrier Backbones’
PacketNetw ork
PacketNetw ork
B B A ccessN etw ork
P O P
POTSBA, PRA
POTSBA, PRA
ADSLHFC
da ta
vo ice
da ta
C orpora te and R esidentia l C P E
P O PPO P P O PP O PPO P
GSMGPRSUM TS
GSMGPRSUM TS
Sw itchedC ircu it N etw ork
(SC N )E S P /M S P
B B A ccessN etw ork
B S P
Sw itchedC ircu it N etw ork
(SC N )
-14 -
S . Treves
N ext G eneration N etw ork (N G N ):generic reference configuration
P acke t N etw ork (P N z)O perator z
xz yzxyO perator x
W x
W x
T*x
T x
Sw itchedC ircu it
Network(SCN x)
U xCustom erPrem ises
(CP x)
NT
TE
O perator y
V y
W y
T y
T*x
Sw itchedC ircu it
Network(SCN y)
U yCustom erPrem ises
(CP y) TE
NT
PacketNetwork(PN x)
AccessNetwork(AN x)
PacketNetwork(PN y)
AccessNetwork(AN y)
CPN CPN
U*xU *x
-15 -
S . Treves
N ew G eneration N etw orks:R eference C onfigurations
PN = P acke t N e tw ork (IP , A TM , M PLS)AN = A ccess N etw ork (AD S L, H FC , PO N +VD SL, LM D S, U TR A N )SC N = S w itched C ircu it N etw ork (PSTN , ISD N , PLM N )x, y, z= D ifferen t ope rators
A N x
S C N x
A N x
A N x
S C N x
A N x
P N x
P N x
P N x
P N x
P N x
P N x
P N z
P N z
P N z
P N y
P N y
P N y
P N y
P N y
P N y
A N x
S C N y
S C N y
A N y
S C N y
S C N y
tx u x
tx u x
tx u x
tx u x
tx u x
tx u x
vx
vx
vx
w x
vx
w x
xz
xz
xz
yz
yz
xy
xy
xy
yz
vy
w y
vy
w y
w y
w y
ty u y
ty u y
ty u y
ty u y
ty u y
tyu y
-16 -
S . Treves
M ain Q oS Techn iquesM ain Q oS Techn iques
-17 -
S . Treves
Q oS A rch itec turesS ing le IP transport provider (1 )
IP
In tserv
▼ C ontro l o f IP ne tw ork Q oS param ete rs▼ Feasib ility o f In tserv E2E▼ D im enson ing o f p re -prov is ioned Trunks
-18-
S . Treves
Q oS A rch itec turesS ing le IP transport provider (2 )
IP
D iffserv
▼ E2E D iffse rv
-19-
S . Treves
Q oS A rch itec turesS ing le IP transport provider (3 )
IP
In tserv
D iffserv
▼ In tserv in the access/edge and D iffse rv in the core
-20-
S . Treves
Q oS A rch itec turesM u ltip le IP transport providers
▼ C onnection path crossing m ultip le transport p rov iders▼ In te rw ork ing of m ultip le com binations of Q oS contro l a rch itectu res
IP
-21 -
S . Treves
In tServ vs D iffServ Techniques
A davantages D isadvantagesFea tures
N etw orkTechn ique
- S tandard ized E2E s igna llingpro toco l (RSVP)
- Requested serv ices offe red(CL and G S )
- RSVP not sca lab le and com plex due toneed for core routers to m ain ta in contro ls ta te for each flow
- Com m on agreeem nt am ong all ISP ’sneeded for E2Econnections (on RSVP use)
- Not su itab le for E2E Q oS
- Sca lab le (focusing on tra fficaggregates w ith sim ila r servicerequ irem ents)
- Requested serv ices offe red
- No signa lling pro toco l to check theava ilab ility o f resources E2E
- Not su itab le for E2E Q oS
- Sca lab le (D iffServ)- S tandard ized In tServ/RSVP
signa lling pro toco l fo rin ter-dom ain
- Com m on agreem ent needed betweenISP ’s on the use of In tServ /RSVP forin ter-dom ain signa lling
In tServ
D iffServ
IntServ in the access& D iffServ in the core
-22-
S . Treves
In tServ m apped on D iffServ
Sender A
accessnetw ork ER1
backbonenetw orkBR1
BR2
accessnetw ork
ER2
R ece ive r Y
In tServD iffServ
In tServ
In tse rv m app ing on D iffserv
-23-
S . Treves
Fixed p ipes m apping In tServ on D iffServ
In tserv flow s en terthe IP backbone th roughborder rou ter BR 4:
1 ) pe rfo rm s the In tserv processing2 ) checks if the re a re su ffic ient am oun t
o f resou rces ava ilab le in the IP backbone .If the flow is accepted, then a ll packe tsa re sent to BR 2
Intserv flow s leavethe IP backbonethough border rou terBR 2
S tatica lly con figured pipes w ith acerta in am ount of bandw id th fromeach ingress rou te r tow ards eachegress rou te r:
* M PLS w ith E -LSPs or L-LSPs* ATM PVC s
BR4
BR3
BR1
BR2
-24 -
S . Treves
E2E Q oSA generic C om m unication Scenario (1)
In tse rv/R SVP (in ter-dom a in s igna ling )
ATM Intse rvD iffse rv 1 D iffse rv 2
D iffserv 1 = fixed p ipesD iffserv 2 = proprie ta ry so lu tionorD iffserv 1 = R SVP aggregationD iffserv 2 = 2 b it resource a lloca tion schem eor ...
-25 -
S . Treves
E2E Q oSA generic C om m unication Scenario (2)
In tse rv/R SVP (in ter-dom a in s igna ling )
D iffse rv 1 D iffse rv 4D iffse rv 2 D iffse rv 3
D iffserv 1 = fixed p ipesD iffserv 2 = proprie ta ry so lu tionD iffserv 3 = over-prov is ionedD iffserv 4 = R SVP aggregation
N o per-flow sta te in :core rou ters o f the 4 dom ainsborder rou ters o f dom ain 3
-26-
S . Treves
C onclus ionsC onclus ions
-27 -
S . Treves
Q oS in N ext G eneration N etw orks
▼ Focus sh ifting from ind iv idua l bu ild ing b locks to E2E netw orkconfigura tions in re la tion to :
◗ C om m unica tion scenarios
◗ N um ber o f the IP transport p rov iders invo lved◗ Q oS contro l a rch itec tu re in use
◗ N um ber o f the IP Te lephony S ervice P rovide rs invo lved
◗ S igna ling , ca ll and A AA contro l a rch itec ture in use
▼ F ixed (w ire line) and m obile (w ire less) ne tw ork environm ents
▼ H etereogeneous classes of tra ffic w ith d iffe ren t Q oSrequ irem ents
-28-
S . Treves
End-to -End Q oS “open” Issues
▼ R eference netw ork configura tions (standard iza tion)
▼ Arch itectu ra l enhancem ents fo r Q oS support (en forcem entand po lic ing)
▼ Protoco l extens ions for Q oS support
▼ E2E Q oS in heterogeneous environm ents:◗ seam less contro l a rch itec tu re for fixed and m obile◗ in te rw o rk ing o f m ulti-adm in is tra tive dom ains (m ultip rov iders)◗ in te roperab ility o f d iffe ren t ne tw orking techno log ies
▼ Q oS support in w ire less subnetw orks:◗ loca tion dependent erro rs◗ tim e verying channe l capacity
▼ D ynam ic custom er cho ice of C lass of Serv ice-29-
Related Documents
