1 1 1-2 Variable

Fig. 11.26. Token ring format.

SD, AC and ED fields are already described. FC field is the Frame control (FC). In FC field, FF bits indicate the frame type. FF = 00 indicates MAC Frame, FF = 01 indicates LLC frame, and FF = 10 and 11 meant for reserved. RR set to 00 and they are reserved bits. ZZZZ = 0000 means a normal buffer and ZZZZ = 0001 indicates express buffer.

DA and SA are destination and source address fields respectively. DA uses the same address format of 802.3. Routing information (RI) is optional. If information field (IF) contains a MAC frame, the frame is called the MAC protocol data unit. If IF field contains an LLC frame, the field is called LLC protocol unit (LPDU). FCS is frame check sequence for error detection and Frame Status field (FS) have the field of 1 byte.

Was this article helpful?

0 0
DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

Get My Free Ebook

Post a comment