DS-TE(Diffserv aware TE)
Kunihiro Ishiguro<kunihiro@ipinfusion.com>

History to reach to DS-TE
from CoS side•
•••
•
•
•

TOS/IP Precedence(RFC791)
IPv4 router requirement(RFC1812)
Diffserv (RFC2474)
MPLS Diffserv(RFC3270)
DS-TE requirement(RFC3564)
DS-TE protocol(draft-tewg-te-proto)
徒花か？それとも必然の流れか？
Proprietary and Confidential to IP Infusion

Usable bit for CoS
TOS/IP
precedence

8 bit

DSCP

6 bit

MPLS Exp bit/
DS-TE requirement

3 bit• 使えるビット数減ってんじゃん...
• 必要なクラスはVoIP/Priority/Normalの３種類くらいだからと誤魔化されているが...
Proprietary and Confidential to IP Infusion

History to reach to DS-TE
from QoS side•
•••••
•

•

RSVP-TE(Intserv復活！)
CR-LDP(死亡)RSVP-TE失敗か？
LSP監視とFast rerouteが追い風に、RSVP-TE再び！
Zero bandwidth セットアップ型
オペレーションフィードバック型
アプリケーション毎に細かい粒度が欲しいが、LSPを一杯張るとscalabilityに不安
Diffservという良いのがあるんじゃん、合体！
Proprietary and Confidential to IP Infusion

TE failed?
TE は失敗したのか？
• MPLS Differve では駄目なのか？
• DS-TEで改善される部分は？
•Proprietary and Confidential to IP Infusion

Implementation•

そもそも実装すべきか？
– おそらくこれでTE技術はある意味デッドエンドだろう– MPLS-Diffservも実装完了している– DS-TEが欲しいという客もヨーロッパ方面にいるし。。。。
– 乗りかかった船なのでやってしまおうかどうしようか。。。。。

Proprietary and Confidential to IP Infusionソースコードと私8Copyright © 2002 IP Infusion Inc. All Rights Reserved.
Company Confidential

DS-TEと私変更が必要なモジュール
RSVP-TE• OSPF/ISIS-TE• CSPF• MPLS DS-TE forwarder•– Russian Doll
– MAM
– MAR

Proprietary and Confidential to IP Infusion

RSVP-TE
MPLS Diffserv RFC3270 is required• A new object CLASSTYPE is defined• MPLS Diffserv があればそれほど大変じゃない•

Proprietary and Confidential to IP Infusion

-05になっても相変わらず
TBDな
OSPF/ISI
S-TEvalue

Traffic Engineering sub-TLVs============================
1 - Link type (1 octet)
2 - Link ID (4 octets)
3 - Local interface IP address (4N octets)
4 - Remote interface IP address (4N octets)
5 - Traffic engineering metric (4 octets)
6 - Maximum bandwidth (4 octets)
7 - Maximum reservable bandwidth (4 octets)
8 - Unreserved bandwidth (32 octets)
9 - Administrative group (4 octets)
GMPLS sub-TLVs==============
11 - Link Local/Remote Identifiers (8 octets)
14 - Link Protection Type (4 octets)
15 - Interface Switching Capability Descriptor (variable)
16 - Shared Risk Link Group (variable)
IPv6 sub-TLVs=============
17 - Neighbor ID (8 octets)
18 - Local Interface IPv6 Address (16N octets)
19 - Remote Interface IPv6 Address (16N octets)
Diffserv aware MPLS sub-TLVs============================TBD - Bandwidth Constraint Model Id (1 octet)
Bandwidth Constraints (4N octets)
10,12,13 are not used by historical reason.

Proprietary and Confidential to IP Infusion

CSPF•••••

実はCSPFが一番面倒
Bandwidth Constraint Modelを考慮する必要がある。
Maximum Reservable Bandwidth
Bandwidth Constraints
Unreserved Bandwidth

Proprietary and Confidential to IP Infusion

Russian Doll

Proprietary and Confidential to IP Infusion

Bandwidth Constraints
Frame Relay?のようなRussian Doll
• MAMはしっかり帯域を制御• どれがどれをプリエンプトできるか？
•Proprietary and Confidential to IP Infusion

InteroperabilityCisco• IP Infusion• An European big router vendor• Internet 2 test using Cisco...
•Proprietary and Confidential to IP Infusion

これから•

Jitterにどう爪をかけるか？
– IGP TE metric•

トラッフィックをどうマッピングするか？
– DBR•

Destination address based routing

– CBR
•

CoS(Diffserv) based routing

– SBR
•

Source address(VPN CE) based routing– .........
•

Proprietary (ECN?)
and Confidential to IP Infusion
Congestion Notification