TRILL Header Extension SimplificationsDonald Eastlake 3rd

Huawei Technologiesd3e3e3@gmail.com

1July 2011

TRILL Data Frame Format

2

Link Specific Header

TRILL HeaderInner Ethernet DA

Inner Ethernet SA

Link Specific Trailer

Payload

VLAN Tag

Inne

r F

ram

e

Header Extensions

July 2011

Table of Contents

• Current Header Extensions/Options– draft-ietf-trill-rbridge-options-05.txt

• Proposed Changes• Summary of Proposal

3July 2011

Current TRILL Header

4

Flags OpLen Hops

Nicknames

| | Flags .

TLV Extensions

Critical Summary bits indicate if it is safe for a transit or egress RBridge that does not implement any extensions to process the frame.

Flow ID

More Flags

July 2011

Current Header ExtensionsFirst 32 Bits

• Present if Ext/OpLng in TRILL Header > 0

5

Flow ID, Non-zero if valid

C. H

-b-H

Bits

Critical Hop-by-Hop Summary Bit Critical Ingress-to-Egress Summary Bit

More Extended Flags

Critical Ingress-to-Egress TLV Option Present

Non-Critical Ingress-to-Egress TLV Option Present

Non-Critical Hop-by-Hop TLV Option Present

NC.

H-b

-H B

its

C. I-

t-E

Bits

NC.

I-t-

E Bi

t

Specified in base protocol

Ale

rt

EC

N

July 2011

Current Header ExtensionsSecond 32 Bits

• If “More Extended Flags” bit is a one, there are 4 bytes of additional extended header flags as follows:

Non-CriticalIngress-to-Egress

CriticalIngress-to-Egress

Non-CriticalHop-by-Hop

CriticalHop-by-Hop

6July 2011

Current TLV Format

• Format of TLV Extensions

Value ……..

Length in 4-Byte Units“Type”

Mutable

Non-Critical

Ingress-to-Egress

7July 2011

Table of Contents

• Current Header Extensions/Options• Proposed Changes• Summary of Proposal

8July 2011

Proposed TRILL Header

9

Flags OpLen Hops

Nicknames

| | | | Flags .

TLV Options

Critical Summary bits indicate if it is safe for a transit, egress, or border RBridge that does not implement any extensions to process the frame.

Alert

ECN

July 2011

Proposed Header ExtendedFlag Bits

• Present if Ext/OpLng in TRILL Header > 0

10

C. H

-b-H

Bits

Critical Hop-by-Hop Summary Bit Critical Ingress-to-Egress Summary Bit

Critical Border RBridge Summary Bit

NC.

H-b

-H B

its

C. I-

t-E

Bits

NC.

I-t-

E Bi

t

Specified in base protocol

Ale

rt

July 2011

NC.

Bor

der B

its

C. B

orde

r Bits

ECN

Proposed TLV Format

• Format of TLV Extensions

Value ……..

Length in 4-Byte Units“Type”

MutableNon-Critical

11July 2011

0 – hop-by-hop1 – border RBridge2 – ingress-egress3 – reserved

Table of Contents

• Current Header Extensions/Options• Proposed Changes• Summary of Proposal

12July 2011

Proposed Actions

• Drop Flow-ID Field for now• Drop 2nd 32-bits of Extended Flags• Add “border” summary bit and TLV extension

bit to accommodate possible future extension of TRILL to multi-level

• Issue Working Group Last Call

13July 2011

ENDDonald Eastlake 3rd

Huawei Technologiesd3e3e3@gmail.com

14July 2011