Tanenbaum

Question

This is a screenshot from tanenbaum my question is, the frame which they are talking about in highlighted text is not an ethernet frame right?  as ethernet frame is used in LAN. So which frame they are talking about in here?

Is it the frame which is used when we are tansmitting in wireless medium from one network to another?

Comments

Data link layer is not just 'Ethernet'. what do you want ? to write things in general sense or every time talk in specific way , like for ethernet this , for PPP this , for HDLC this....

book talked about general scenario. They talked about data link layer frame.

why do you think , like DLL transfers data only in LAN, it transfer data in WAN also (b/w directly connected nodes)

Answer 1

just have one important thing to figure out....here they say ACK.....100% its not ETHERNET frame ...because in ETHERNET we have no ACK...

generally they are talking abut the frames of data.....when we have dedicated lines and we are using protocals like SLIDING window...or stop and wait ...(in sliding we may use SR or GBN...)

only with the help of ACK you can gurantee that yes its not ETHERNET frame...

Comments

yea thats what i thought thnku sir