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"MULTIPLEXING" - PRETENSIOUS VERB

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the verb in the opening sentence - multiplexing - i suggest could be replaced. Unnecessarily obtruse. Something like "adds more protocols" would do fine. —Preceding unsigned comment added by Retroguy90 (talkcontribs) 01:25, 25 June 2008 (UTC)[reply]

How is it that "multiplexing" can be "pretentious"? Please explain. — Dgtsyb (talk) 03:11, 26 June 2008 (UTC)[reply]

Calculation of reduction of available payload wrong?

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"On Ethernet, this reduces the size of the available payload for protocols such as the Internet Protocol to 1492 bytes" seems to be wrong: the SNAP header is 8 bytes, two of which are stored in the ethernet EtherType field (0xAAAA, the DSAP and SSAP). This leaves 6 bytes overhead when using a SNAP header reducing the payload to 1494 (not 1492) bytes (down from 1500 of ethernet framing without SNAP), or is my math wrong in some way? User:Runtux —Preceding undated comment added 14:52, 12 May 2009 (UTC).[reply]

No, this point "two of which are stored in the ethernet EtherType field" is incorrect. The 802.2 LLC header goes after the IEEE 802.3 Type/Length field (which contains the length when 802.2 LLC header is used - it is IEEE 802.3 header, not Ethernet-II header) of the Ethernet header and SNAP header follows the 802.2 LLC header. So there is really room for 1492 bytes of payload. Kolarp (talk) 20:20, 27 May 2020 (UTC), reworked 13:08, 17 Jun 2020 (UTC)[reply]

Poor Grammar in beginning sentences

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The first few sentences use poor English grammar which makes them more difficult to understand than they should be. I am not an expert in SNAP so I will leave my corrections here. If approved by the editors I will add them.

The Subnetwork Access Protocol (SNAP) is an extension of the IEEE 802.2 Logical Link Control (LLC) to distinguish many more protocols of the higher layer than by using of the 8-bit Service Access Point fields (LSAP) present in the IEEE 802.2 header.

The SNAP and LSAP fields are added to the packets at the transmitting node in order to allow the receiving node to pass each received frame to an appropriate device driver which understands the given protocol.

Background

The Sub-Network Point of Attachment (SNPA) is the data-link address used in IS-IS protocol to reach the neighbor on a broadcast media. This can be compared to the use of Ethernet links using the Mac Address of the neighbor.[1]

References

  1. ^ Soricelli, Joseph M. with John L. Hammond; et al. (2003). JNCIA : Juniper Networks Certified Internet Associate : study guide. San Francisco: SYBEX. ISBN 0-7821-4071-8.

Nicodemus (talk) 15:28, 15 May 2017 (UTC)[reply]

That's SNPA, not SNAP; they're not related. That sentence was introduced in this edit; I'll just remove it. Guy Harris (talk) 18:23, 22 May 2017 (UTC)[reply]