IOS family naming

Arie Vayner arievayner at
Tue Jan 26 21:21:27 UTC 2010


I could not find a good link, but let me give you some info on SG, SGA, EW
and EWA.
All these trains are for the 4500 family (including 4900). They are just
different generations.

The EW (and then EWA) were the older trains for 4500, which were replaced by
the SG trains.
If I am not too wrong EW/EWA was new around 2004.

SGA was the 1st release for the SG train, but later releases are not called
SGB/SGC, but are just marked SG, so you get 12.2(31)SGA as the first release
(with 12.2(31)SGA1, 12.2(31)SGA2 etc being maintenance releases, with SGA11
scheduled to be released in a few weeks).

The later SG releases are numbered as 12.2(37)SG, 12.2(40)SG, etc - and we
have 12.2(53)SG as the latest one. Each such release brings in new features,
and has its own maintenance releases (so it would be 12.2(53)SG1,
12.2(53)SG2 etc, with 12.2(53)GS2 being scheduled for the Q2CY10)

Hope this gives you a better view.


On Tue, Jan 26, 2010 at 10:35 PM, Andrey Gordon <andrey.gordon at>wrote:

> Hi List,
> Anyone recalls ever seeing the IOS naming convention document. In
> particular
> I'm interested in differences between families and trains.
> This is all I found:
> But im looking for something a bit more recent maybe? Can figure out
> differences between say SG, SGA, EW and EWA.
> A link to the cipher would certainly help.
> -----
> Andrey Gordon [andrey.gordon at]

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