hálózati és szolgáltatási...

Hálózati és Szolgáltatási Architektúrákhttps://www.vik.bme.hu/kepzes/targyak/VITMM130/

Architectures of Networks and Services

Mérnök informatikus szak, MSc képzésHálózatok és szolgáltatások szakirány

Dr. Cinkler Tibor

cinkler()tmit.bme.hu

Egyetemi Docens

BME TMIT

Dr. Vidács Attila

Egyetemi Docens

BME TMIT

5. alkalom

2009. március 7., Hétfı, IB.138, 8:30-10:00

http://opti.tmit.bme.hu/~cinkler/HSzA/

http://hsnlab.tmit.bme.hu/~vidacs/education/vitmm131/2009/vitmm131-2009.htm

TMIT: Távközlési és Médiainformatikai Tanszék

56

Idaig jutottunk

� Magyar Telekom Menedzselıközpont látogatást

� Országos Mőszaki Múzeum, www.omm.hu

(+36-1) 204-4092 , 1117 Budapest, PrielleKornélia . u.10. (Szerémi út - Prielle Kornélia u. sarok)

� várbéli Telefónia Múzeum:

http://www.postamuzeum.hu/stores/item/10.html

57

MPLS történelem

� ATM

� MPOA

� MPLS

� MPLambdaS

� GMPLS

� T-MPLS

� MPLS-TP

58

MultiProtocol Label Switching (Többprotokollos címkekapcsolás)

� Egységes IP/MPLS kontroll� Valamivel egyszerőbb mint ATM� Csökkentett cimketér használat FEC révén (Forwarding Equivalence

Class)� Cimke lecserélés (Swapping) és többszintő felülcimkézés (Stacking)� ATM-hez képest nem sok új� Topológia-centrikus vagy forgalom-centrikus (vezérelt)� QoS kérdések még nyitottak� TE-t és VPN-t támogatja� IPoMPLS: Peer Model !

� RSVP-TE� CR-LDP

MPLS

59

MPLS� LER: Label Edge Router

� LSR: Label Switching Router

� FEC: Forwarding Equivalence Class

� LSP: Label Switched Path

� Label Swapping

LERLSR

IP Router

60

Label „Stacking” vagy „Swapping”?

� Ha „vermelünk” sok réteg lesz!� Hierarchikus LSP beágyazás (encapsulation, embedding, nesting)

LSP1LSP2LSP3LSP4

LSP1

LSP2

LSP3

LSP4

dataStacked Headers

62

Az IP fejrész az MPLS fejrész� Útvonalválasztás (routing) és adategység továbbítás (forwarding)

Service Type

Fragment Offset

VERS HLEN Total Length

Identification Flags

TTL Protocol Header Checksum

Source IP Address

Destination IP Address

Options Padding

D a t a

D a t a

D a t a

...

Label

Label

Label

TTL

CoS S

0 716 310 8

63

Routing, TE & Resilience →→→→manapság:

DP n+2

DP n+1

DP n

DP n-1

CP n+1

CP n

CP n-1

client

server

client

serverclient

server

CP n+2MP n+2

MP n+1

MP n

MP n-1

Kliens-szerver megoldás

Részben kézzel

64

Routing, TE & Resilience→→→→ vágy:

DP n+2

DP n+1

DP n

DP n-1

CP

MP

Integrált, automatikus, elosztott!

Függıleges együttmőködtetés vagy integrálás?

65

Multi-Layer (Vertical) Interconnection Models

(RFC 3717)

� Overlay Model� The control of layers is independent� “Server-Client” approach� like “classical IP over ATM” or “MPOA” models� optical layer can be statically configured

� Peer Model� Interoperable control plane (e.g., Optical layer is also IP addressable)

� Augmented (Hybrid)� Something between� Hides confidential provider information� Some information of one routing instance passed through the other� E.g., IP addresses could be carried within the optical routing protocol

66

Vertical Integration:

Multi-Layer Integrated Model

� The layers owned by the same operator

� Full interlayer information exchange possible

(No interface needed in between)

� Can be operated by a single CP and a single MP

� Routing, TE, Resilience → more complex

� MRN: Multi Region Network (Region: interconnected nodes of the same networking technology – a bit

misleading)

67

MLN/MRN� www.ietf.org/rfc/rfc5212.txt

� Shiomoto, K., Papadimitriou, D., Le Roux, JL., Vigoureux, M., and D. Brungard, "Requirements for GMPLS-Based Multi-Region and Multi-Layer Networks (MRN/MLN)", RFC 5212, July 2008. � „In GMPLS, a switching technology domain defines a region, and a

network of multiple switching types is referred to in this document as a multi-region network (MRN).”

� Traffic Engineering Database (TED) – Itt van minden infó, ami egy egységes GMPLS síkhoz kell

� Interface Switching Capability (ISC) - „introduced in GMPLS to support various kinds of switching technology in a unified way [RFC4202]”

� Virtual Network Topology (VNT)

� lower-layer FA-LSP létrehozása: static (pre-provisioned) vagy dynamic (triggered)

� (FA-LSP: Forwarding Adjacency Label Switched Path)

68

MLN/MRN� www.ietf.org/rfc/rfc5339.txt

� Ed.: JL. Le Roux, D. Papadimitriou, "Evaluation of Existing GMPLS Protocols against Multi-Layer and Multi-Region Networks (MLN/MRN)", RFC 5339, September 2008� MIB modules

� model and control of GMPLS switches [RFC4803]

� control and report on the operation of the signaling protocol [RFC4802]

� a MIB module for managing TE links [RFC4220] (interesting for MLN!)

� Oki, E., Le Roux , J-L., and A. Farrel, "Framework for PCE-Based Inter-Layer MPLS and GMPLS Traffic Engineering", Work in Progress, June 2008.

� Miyazawa, M., Otani, T., Nadeau, T., and K. Kunaki, "Traffic Engineering Database Management Information Base in support of MPLS-TE/GMPLS", Work in Progress, July 2008.

69

Vízszintes Tagoltság: Többtartományos Hálózatok

� OSPF+BGP-4, oBGP

� PNNI, oPNNI

� PCE: Path Computation Element

Két szempont:

� Access (Aggregation) – Metro – Core (Backbone, Transport)

� Vagy Több szolgáltató

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PCE: Path Computation Element

� Egy vahgy több PCE tartományonként� TED: Traffic Engineering Database

� PCEP: PCE Communication Protocol

� PCC: Path Computation Client

� Tartományközi útvonalválasztás (Path Computation)� Elosztottan

� Tartományok belsejét nem ismerjük!

� 2 módszer:� Backward Recursive PCE-based Computation (BRPC) draft-ietf-pce-brpc-09

� VSPT (Virtual Shortest Path Tree)

� [RFC5152] Vasseur, JP., Ayyangar, A., and R. Zhang, "A Per-Domain Path Computation Method for Establishing Inter-Domain Traffic Engineering (TE) Label Switched Paths (LSPs)", RFC 5152, February 2008.

PCE

PCC1 PCC2

PCEP

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Multi-Domain Path Computation (BRPC) 1/2Forrás: Shinya Ishida, Yohei Iizawaa, Itaru Nishiokaa, Souichiro Arakia: Experimental Performance Evaluation of Inter-Domain Path Provisioning with Multiple PCEs, APOC 2008

72

Multi-Domain Path Computation 2/2Forrás: Shinya Ishida, Yohei Iizawaa, Itaru Nishiokaa, Souichiro Arakia: Experimental Performance Evaluation of Inter-Domain Path Provisioning with Multiple PCEs, APOC 2008

73

Two different vendors

Management Plane Management Plane

Client

User/Data/Transport/Forwarding PlaneUser/Data/Transport/Forwarding Plane

Control PlaneControl Plane

Client

CC

CCCC

CC

CC

CCCC

NMI-T

NMI-C

UNI

CCI

Vertical interconnection / integration

E-NNI

IntraVendor

I-NNI

InterVendor

I-NNI

CC: Connection Controller

CCI: Connection Controller Interface

NMI: Network Managemnt Interface

NMI-C: NMI for the CP

NMI-T: NMI for the Transport Plane

UNI: User to Network Interface

NNI: Network to Network or Network Node Interface

I-NNI: Interior NNI (Intra and Inter Vendor I-NNI)

E-NNI: Exterior NNI

UNI

74

Heterogén hálózatok: sok ‘M’ mint Multi� Divergens technológián alapuló konvergens hálózat?� Heterogén technológián alapuló homogén hálózat?

� MS: Multiple Services with Different Traffic, QoS, QoR Requirements, multiple routing, multicasting solutions, MultiGranularity (Multi-Service, Multi-Rate, Multi-Quality, Multi-Routing)

� ML: Multiple Interconnected or Integrated Layers (Multi-Layer)� Vertical Integration?

� MD: Multiple Domains (Multi-Domain)� Horizontal Integration?� Multiple Providers� Multiple Vendors (interoperability)

� Multiple Technologies (Multi-Region / Multi-Technology)� From wireless mobile to wireline fixed (FMC), electronic-optical, circuit-

packet, computer/data and voice/telecom, etc.

� Unified Control and Management!!!

75

Circuit vs Packet “Switching”?

E.g.: SDH, OTN, ASON

� QoS

� For CBR traffic

� Poor granularity

� Peek rate allocation

� Allocated even if unused

� More wavelengths needed

� Slower provisioning

� Negligible transmission delay

E.g.: IP, OBS, OPS

� QoS problems

� For VBR traffic

� Better granularity

� Statistical multiplexing

� Fewer wavelengths needed

� Fast provisioning

� Larger transmission delays

Megannyiadszor...

Együtt a kettıt!!!

76

Global Information Infrastructure (GII)

Next Generation Network (NGN)

Source: ITU-T Y.2011 General principles and general reference Model for NGNs: – Separating services and transport in NGN– NGN Basic Reference Model (NGN BRM)

NGN Transport

NGN Services

Eg.,Voice Telephony Services (audio, etc)

Eg,, Data Services (e.g.,WWW, e-mail, etc)

Eg., Video Services (TV, movie, etc)

User Plane

Control Plane

Management Plane

NGN Service Stratum

User Plane

Control Plane

Management Plane

NGN Transport Stratum

77

Szolgáltatás és annak „szállítása” elkülönül...

� Nem egy szép homogén hálózat építése már a cél!

� Hanem bármilyen részhálózatok újrahasznosítása, olcsó bıvítése, általános célra

� Bármilyen forgalom (szolgáltatás, tartalom) bármilyen hálózat felett!

� A hálózat már csak azért kell, hogy a szolgáltatások/szolgáltatók több hasznot termelhessenek...

� A cél szentesíti az eszközt!� A hálózat csak „csomagolása” a szolgáltatásnak� De minıségért (QoS) is felelıs...

78

Ethernet optika felett a gerinchálózatban

PTT megoldások

� CCE / CGE: Carrier Class/Grade Ethernet

� PTT: Packet Transport Technologies� CET: Carrier Ethernet Transport� Solutions:

� MPLS-TP� PBB-TE (IEEE 802.1Qay )� stacked VLAN� PBB (IEEE 802.1ah)� VPWS (Pseudowire or PWE3) � VPLS using Label Distribution Protocol signaling� VPLS using Border Gateway Protocol signaling

� T-MPLS → MPLS-TP (Transport MPLS → MPLS – Transport Profile)

� Networks2008 konferencia: C. Gruber, A. Autenrieth - Tutorial www.networks2008.hu/data/upload/file/Tutorial/T7_Gruber_Autenrieth.pdf

� (MPLS 2008 konferencia: L.Andersson - Tutorial http://www.isocore.com/mpls2008/program/tutorials.htm)

79

What is “Carrier Grade”?

80

Transport Network – Definition and Requirements(Forrás: T-MPLS Technology Overview, Stéphan Roullot, October 2007, Alcatel-Lucent)

Scalability

Reliable aggregation and transport of any client

traffic type, in any scale, at the lowest cost per bit

Transport Network

Quality Cost-EfficiencyMulti-service

Ability to support any number of client traffic instances whatever network size, from access to core

Ability to ensure that client traffic is reliably delivered at monitored

performance e2e

Ability to deliver any type of client traffic (transparency to

service)

Acting as server layer for all the rest by keeping processing complexity low and operations easy

Transport values have evolved through long TDM evolution

They hold through transition to packets

� Layering� Partitioning

� Client agnosticism(any L1, L2, L3)

� Connection oriented� OAM, resiliency� Traffic engineering, resource reservation

� CAPEX: low protocol complexity

� OPEX: multilayer ops across packet/TDM/λ

81

Transport Network vs. Service Network: Horizontal View (Forrás: T-MPLS Technology Overview, Stéphan Roullot, October 2007, Alcatel-Lucent)

Service Edge

Home

IPTV, 3G, Storage, etc.

Access

BusinessFiber Fiber

Metro Aggregation

Core Aggregation

Transport Network

User Application

Intelligent Access

Intelligent CPEEfficient Transport (PKT, TDM, λ)

Rich Subscriber & Service-

Awareness, IP Routing

IP Routing

Protocol complexity

BW efficiency

OSI layers

Efficient Transport (PKT, TDM, λ)

82

Placing appropriate functions in the network where it makes sense

Separation between service and transport for overall cost-efficiency

Transport Network vs. Service Network: Vertical View(Forrás: T-MPLS Technology Overview, Stéphan Roullot, October 2007, Alcatel-Lucent)

Service Network

Transport Network

OSI layers, Cost

Geographic Reach

Different roles, features (and costs):

Fiber

User/Application

1

2

3

4

5

6

7

IP

Protocol Complexity ($$$)Detailed Service Management/QoSLocalizedService & Subscriber-AwarenessHigh # EntitiesDeep-Touch Service Richness & OAMState-full, Short holding times

Bandwidth Efficiency ($)Effective Bandwidth Management/QoSUbiquitousTransparency (Service)-AwarenessLow # EntitiesResilience, Robust OAMState-less, long holding times

83

Transport Network - Portfolio Strategy(Forrás: T-MPLS Technology Overview, Stéphan Roullot, October 2007, Alcatel-Lucent)

Data Capacity

Feature richness

SONET/SDH rings

DCS

WDM pt-to-pt

< 2000 > 2006

Key drivers• Capacity/Scalability

• Performance

• Reliability/Availability

Key drivers• Changing service mix

• Bandwidth optimization

• Automation

Key drivers• Capacity/Scalability

• Operational efficiency

• Reliability/Availability

NG-SONET/SDH

ION

ROADM

Full-packet transport

Transparent photonics

2006

Multi-service platform enabling efficient transport of data on today’s networks

Evolution path towards full packet and photonic networking

84

PW / T-MPLS Interworking: Data Plane & OAM Perspective(Forrás: T-MPLS Technology Overview, Stéphan Roullot, October 2007, Alcatel-Lucent)

T-MPLSNetwork

MPLS PW MPLS PWClient

Client OAMBFD (e2e) / MH-VCCV

1:1 1:1MPLS PW ≡ T-MPLS channelT-MPLS channel

T-MPLS channel OAM …G.8114 (Tandem Connection)

N:1 1:NMPLS tunnel MPLS tunnelT-MPLS path TMPLS path TMPLS path

T-MPLS path OAMG.8114

TMPLS pathN:1 1:N

G.8114

BFD BFD

BFD: Bidirectional Forwarding Detection (Hello Protocol-hoz hasonló, de alsó rétegben)PW: Pseudowire, RFC 4448, „An Ethernet PW emulates a single Ethernet link between exactly two endpoints”

85

IP/MPLS Backbone Routers Interconnection(Forrás: T-MPLS Technology Overview, Stéphan Roullot, October 2007, Alcatel-Lucent)

PE(P) PE(P)T-switch

T-switch

DP: T-MPLS

CP:GMPLS

OAM: T-MPLS

Protection: T-MPLS/GMPLS

T-MPLS path with

T-MPLS label swap

MPLS tunnel with

MPLS label swap

DP: MPLS

CP: MPLS

OAM: MPLS

Protection: MPLS

DP: MPLS

CP: MPLS

OAM: MPLS

Protection: MPLS

� T-MPLS is an overlay network with respect to MPLS

� PE-P routers are aware of border T-switch only (Provider Edge)

� The interface between a border T-switch and a PE-P router is a MPLS interface

� Two different MPLS/GMPLS IWF can be defined: “trusted” and “not trusted”

T-MPLS Network

MPLS

T-MPLST-MPLS T-MPLS

MPLS

ETY ETY ETY ETY ETYETYETY ETY

MPLS MPLS

T-MPLS

ETYETY

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