Title: | DEChub/HUBwatch/PROBEwatch CONFERENCE |
Notice: | Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7 |
Moderator: | NETCAD::COLELLA DT |
Created: | Wed Nov 13 1991 |
Last Modified: | Fri Jun 06 1997 |
Last Successful Update: | Fri Jun 06 1997 |
Number of topics: | 4455 |
Total number of notes: | 16761 |
Hi! I'm just wondering how does the IP services functionality work? Does it work differently according to which type of module is providing it? As far as I understood, when a module is providing IP services it is providing a MAC address to the MAM. But which MAC address ? If it is one among the ones it is using for its ports we would get an ARP problem. Does it have a "spare" MAC address for IP services? Thanks. Pedro
T.R | Title | User | Personal Name | Date | Lines |
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3546.1 | See Note 581 | NETCAD::BRAGDON | Tue May 21 1996 14:00 | 1 | |
See Note 581 | |||||
3546.2 | NETCAD::MILLBRANDT | answer mam | Tue May 21 1996 14:17 | 13 | |
It is up to each type of hub module supporting IP Services as to which MAC address handles the traffic for the served hub address. 900 repeaters have 1 MAC; on the PORTswitch I think you get to choose which port group it belongs to. As best I recall, the DECswitch900 has one generic MAC (e.g. 11-22-33-44-55-60) and each of its ports are addressed one higher (11-22-33-44-55-61, etc), but each port also serves the generic MAC. Check the Owner's Manual for your module to see what it does. Once the message has been received and is being passed to the IP layer, all modules use common code for IP services. Dotsie | |||||
3546.3 | NETCAD::GERHARDT | Out of Control | Thu May 23 1996 11:45 | 11 | |
the mam uses the MAC address of the module. they have different IP addresses. the receive task of the module looks at the ip address in the frame. if it is local it is processed. if it is for the mam's ip address it is forwarded. doties' explaination about the decswitch 900 is correct, expect that 11-22-33-44-55-60 is a multicast address. ^ this digit has to be even to be unicast. | |||||
3546.4 | Thanks | LEMAN::PAIVA | Hawkeye - Network Support @GEO | Thu May 23 1996 12:39 | 15 |
Thanks for the infos. In fact I had a false way of thinking because I wrongly considered the problematic of 1 IP to 2 MACs, which would have problems with ARP... Shame on me! >doties' explaination about the decswitch 900 is correct, expect that > 11-22-33-44-55-60 is a multicast address. > ^ this digit has to be even to be unicast. Of course, but I think Dotsie just wanted to keep it simple. DEC and all other vendors are lucky enough to have unicast OUIs 8-) Cheers, Pedro |