SRW2008 Adding Extra Byte To Packet

[tom.bramer]

I have an SRW2008 switch, and it appears to be adding an extra byte at the end of some packets.  The value of the byte is always 0x0F.  Can someone tell me why this might happen, and how can I configure the switch to stop doing this?

[tom.bramer]

Additional information:

I also have two SD208 switches, one with firmware version 1.1 and one with firmware version 3.0.  The one with 1.1 also adds the extra byte (sometimes-same as the SRW2008), but the one with 3.0 does not, and it works fine.

[Gerald Vogt]

And how do you know there is an extra byte? Do you have packet dumps available from the sender and receiver?

[tom.bramer]

I do not have packet dumps.  We have in-house designed hardware that is acting as the receiving terminal, and our hardware designer (by inspecting firmware registers during a transfer) was seeing the extra byte (always 0x0f, when it happens).  This causes his firmware to malfunction.  The problem goes away when we use the SD208 switch with firmware version 3.0.  A Netgear (GS105) switch also works fine.  A SD208 switch with firmware version 1.1 behaves the same as the SRW2008 (i.e. sometimes adds the extra byte).