Browse Prior Art Database

Comments on "Byte size for connections" (RFC0176) Disclosure Number: IPCOM000004010D
Original Publication Date: 1971-Jun-14
Included in the Prior Art Database: 2000-Sep-12
Document File: 3 page(s) / 7K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

A.K. Bhushan: AUTHOR [+4]


There are at least the following three views on the use of byte size for network connections*:

This text was extracted from a ASCII Text document.
This is the abbreviated version, containing approximately 45% of the total text.

Network Working Group A. Bhushan, MIT

Request for Comments #176 R. Kanodia, MIT

NIC #7100 R. Metcalfe, MIT

Categories: C and D J. Postel, UCLA

14 June 1971

Comments on Byte Size for Connections


There are at least the following three views on the use of

byte size for network connections*:

1) Byte size should not be used at all.

2) Byte size is solely for the convenience of NCP's.

3) Byte size choice is a user-level prerogative.

According to the first view, network connections are bit

streams, and messages should contain bit counts (i.e., a

byte size of 1). This view existed before the "Glitch Cleaning"

of RFC 107, and was discarded in favour of byte stream because

of stated reasons of efficiency in storage management and

message concatenation.

The second view represents a special interpretation of

RFC 107. According to this interpretation, byte size is

entirely a 2nd level (i.e., NCP) issue. There is no require-

ment that 3rd level user processes be able to specify byte size.

This view is indicated in RFC 151 by Shoshani.


* Byte size for connection is the byte size selected by

sending NCP, as explained in RFC 107 (Output of Host-Host

Protocol Glitch Cleaning Committee).

According to the third view user processes are always

allowed to choose byte size for connection, either explicitly

(specify a specific byte size parameter) or implicitly (byte

size depends on I/O mode). An NCP is allowed to use a default

byte size, if the user does not specify it.

The Correct View


The third view should be considered the correct interpre-

tation of RFC 107. In fact, RFC 107 states on page 2, "the

choice of the byte size for a connection is a 3rd level protocol

issue." To be consistent with TELNET, ICP, and other 3rd

level protocols which require that a specific byte size be

used for connection, it is imperative that corresponding 3rd

level processes be able to specify (and_impose) a particular

byte size to the NCP. NCP implementors should take note of it.

On Specifying Fixed Byte Sizes in 3rd Level Protocols


Holding the view that byte size choice is a 3rd level

issue, we are still faced with the following two questions.

First, is it appropriate for 3rd level protocols to legislate

a specific byte size for all connections using that protocol?

Second, if it is appropriate to specify byte size, then what

should this choice be?

There are two arguments in favour of using specific

byte size in 3rd level protocols. First is that a potential

mismatch problem exists because RFC 107 does not require

that NCPs be capable of handling all byte sizes 1 through 255.

Using a fixed...