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TIPC based TML for ForCES Protocol

Jon MaloyShuchi ChawlaHormuzd KhosraviFurquan AnsariJamal Hadi Salim

63rd IETF Meeting, Paris

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Topics

Similarities/Differences to TCP/IP TML Control/Data Channel Model Address Mapping Multicast Fulfilling Requirements

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Similar, multiplex/demultiplex modelNo TML encapsulation Control channel based on reliable TIPC connection Data channel based on “best effort” TIPC connection

–No “transport-on-transport” problem

Limited to closed LAN networks (one chassis) for now Performance No configuration required

–FE/CE ids map directly to TIPC addresses

Neighbour detection for free

Comparison to TCP based TML

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Connection/Channel Model

FE Object

CE Object

FE

CE

TIP

CLFB 1 LFB 2

FB X FB Y

Connectionless SOCK_RDM TIPC

“Best Effort” Connection” as Data Channel

Reliable Connection” as Control Channel

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Address Mapping

FE 5

CE 8

TIP

C

TIPC API

TML APItml_init(ce=8)

bind(CE_CTRL_TYPE,8)

CE Object

TIPC API

TML API tml_open(ce=8)

connect(CE_CTRL_TYPE,8) FE Object

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Address Mapping

FE Object

CE Object

FE 5

CE 8

TIP

CLFB 6,2

FB Ysend_ctrl(fe = 5,lfb_type=6, lfb_inst = 2)

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Address Mapping, Multicast

FE 5

CE 8

TIP

C

TIPC API

TML API CE Object

TIPC API

TML APIFE

Objectbind(mcid,5)

tml_join(mcid)

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Address Mapping,Multicast

FE Object

CE Object

FE 5

CE 8

TIP

CLFB 6,2

FB Ysend_mc(mcid=4,lfb_type=6, lfb_inst = 2)

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Reliability– Reliable transport in all modes

– Can be made unreliable per socket/direction

Security– Only secure within closed networks.

– No explicit authentication/encryption support yet, but planned

– Not IP-based, no router will forward TIPC messages!!

Congestion Control– At three levels: Connection/Transport, Signalling Link and Carrier

level– Will give feedback to PL layer if connection is broken

Multicast/Broadcast– Supported

Fulfilling Requirements(1)

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Timeliness– Immediate delivery (No Nagle algorithm)

– Inter-node delivery time in the order of 100 microseconds

HA Considerations– L2 link failure detection and failover handled transparently for user

– Connection abortion with error code if no redundant carrier available

– Peer node failure detection after 0.5-1.5 seconds

Encapsulation– No TML layer encapsulaton

Priorities– Supports 4 message importance priorities, determining congestion

levels and abort/rejection levels

Fulfilling Requirements(2)

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Questions ???

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To Consider…

FE 5

CE 8

FB Y

TIPC API

FORCES API

forces_bind(lfb_type=6,inst=2)

bind(6,2)LFB 6,2

FE Object

CE Object

TIP

C

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To Consider…

FE 5

CE 8

TIPC API

FORCES API

FB Y

TIPC API

FORCES API

forces_recv()

recvfrom()LFB 6,2

FE Object

CE Object

TIP

C

forces_send([fe = 5,] lfb_type=6,inst = 2)

sendto([5],6,2)

Control traffic: Reliable connectionless (SOCK_RDM)

Data traffic: Best Effort connectionless (SOCK_DGRAM)

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Should generic PL layer according to spec really be mandatory ??

A service description of the ForCES communication service may be sufficient, and less restrictive

To Consider…