RE: FCIP: NAPTs Solution Proposal (issue from Irvine, CA Interim meeting)

["Murali Rajagopal" <muralir@lightsand.com>]

Few minor comments regarding the write up. See embedded comments in the
snipped version of this email from Ralph:

-----Original Message-----
From: owner-ips@ece.cmu.edu [mailto:owner-ips@ece.cmu.edu]On Behalf Of Ralph
Weber
Sent: Wednesday, October 24, 2001 2:44 PM
To: IPS Reflector
Subject: FCIP: NAPTs Solution Proposal (issue from Irvine, CA Interim
meeting)

.....
An FCIP Entity that receives a TCP Connect request SHALL use the
contents of the FC Fabric Entity World Wide Name and FC/FCIP
Identifier fields to determine the FCIP_LEP to which the FCIP_DE
associated with the TCP connection is assigned. This may be an
existing FCIP_LEP or a new FCIP_LEP, depending on whether the
FCIP Entity has received the same FC Fabric Entity World Wide Name
and FC/FCIP Identifier field values before. If an FCIP Short Frame
is received on a TCP connection that has already been assigned to
an FCIP_LEP, the FC Fabric Entity World Wide Name and FC/FCIP
Identifier fields SHALL be ignored.
The above last sentence needs some more elaboration as to how a SF can
arrive on an existing FCIP_LEP.

The Connection Usage Flags field identifies the types of SOF values
[FC Encapsulation] to be carried on the connection as shown in
figure z.

|------------------------------Bit------------------------------|
|                                                               |
|   31      30      29      28      27      26      25      24  |
+---------------------------------------------------------------+
|  SOFf | SOF?2 | SOF?3 |                Reserved               |
+---------------------------------------------------------------+

   Fig. z -  Connection Usage Flags Field Format

If the SOFf bit is one, then frames containing SOFf are intended
to be carried on the connection.

If the SOF?2 bit is one, then frames containing SOFi2 and SOFn2 are
intended to be carried on the connection.

If the SOF?3 bit is one, then frames containing SOFi3 and SOFn3 are
intended to be carried on the connection.

All or none of the SOFf, SOF?2, and SOF?3 bits MAY be set to one.
If all of the SOFf, SOF?2, and SOF?3 bits are zero, then the types
of FC Frames intended to be carried on the connection has no
specific relationship to SOF code.

The FCIP Entity SHALL NOT enforce the SOF usage described by
the Connection Usage Flags field and SHALL only use the contents
of the field as described below.

The Connection Usage Code field contains Fibre Channel defined
information regarding the intended usage of the connection as
specified in FC-BB-2.

The FCIP Entity SHALL use the contents of the Connection Usage
Flags and Connection Usage Code fields to locate appropriate QoS
settings in the "shared" database of TCP connection information
(see 8.1.1) and apply those settings to a newly formed connection.
If an FCIP Short Frame is received after QOS settings have been
established, the Connection Usage Flags and Connection Usage Code
fields SHOULD be ignored.
Use of Connection Usage Flags and Code Fields need some explanation

For each new incoming TCP Connect request received, the FCIP Entity
SHALL send the contents of the FC Fabric Entity World Wide Name,
FC/FCIP Identifier, Connection Usage Flags and Connection Usage
Code fields to the FC Entity along with the other new connection
information.


[Change 2] In 5.6.1, add the pFlags field definition and require
all FCIP Encapsulated Frames except Short Frames to have SF equal
to zero.  Note: Some part of the pFlags description above will
go in 5.6.1 not in the new section but the description above is
structured for easier reading in this proposal.


[Change 3] Some place in 5.6 (the description of the FCIP_DE),
require the FCIP_DE to pass all FCIP Short Frames to the Control
& Services Module.


[Change 4] In 7.1.3 and 7.1.4 (the two sections where TCP Connect
requests are generated), require the FCIP Entity to:

  1) Acquire the Connection Usage and other information from the
     "shared" database (see section 7.1.1);
  2) Send a FCIP Short Frame as the first bytes passing through
     the Encapsulated Frame Transmitter Portal following establishment
     of a TCP connection;
May be a good idea to describe the echo protocol a little more clearly
stating its purpose and capabilities and any possible future extensions.
  3) Compare the first bytes received through the Encapsulated Frame
     Receiver Portal to the FCIP Short Frame sent and close the TCP
     connection if the bytes are not an FCIP Short Frame whose
     contents (words 7 through 13 inclusive) exactly match the FCIP
     Short Frame passed through the Encapsulated Frame Transmitter
     Portal.

 .....