I would still use a /30 mask if I was using unregistered IP's. If I was using standard IP's then maybe I would think about using the /31.
-----Original Message----- From: Symon Thurlow [mailto:sthurlow@;webvein.com] Sent: Saturday, October 12, 2002 4:45 PM To: [EMAIL PROTECTED] Subject: RE: can I use a /31 subnet to the link between 2 routers eth [7:55469] Thanks! I stand corrected. Cheers, Symon -----Original Message----- From: Bob McWhorter [mailto:bob@;oregontrail.net] Sent: 12 October 2002 17:06 To: [EMAIL PROTECTED] Subject: RE: can I use a /31 subnet to the link between 2 routers eth [7:55460] Symon, Reference RFC 3021 Using 31-Bit Prefixes on IPv4 Point-to-Point Links HTH -----Original Message----- From: [EMAIL PROTECTED] [mailto:nobody@;groupstudy.com] On Behalf Of Symon Thurlow Sent: Saturday, October 12, 2002 7:59 AM To: [EMAIL PROTECTED] Subject: RE: can I use a /31 subnet to the link between 2 routers eth [7:55454] Well, if you work it out: Obviously the first three octets wil be all 1's, so if you look at the last octet: 11111110 Which = 254. This only leaves you with 2 addresses per subnet, and since you need one address for the Network address and one for the Broadcast address, you no longer have any addresses you can actually use. A 30 bit subnet, where the last octet= 11111100 Equals 252. This means you have 4 addresses per subnet. Taking away one address for the Network and one for the Broadcast address, this leaves you one address for each end of the link. So I am not sure how you could use a /31. Symon -----Original Message----- From: bbfaye [mailto:heva@;163.com] Sent: 12 October 2002 14:54 To: [EMAIL PROTECTED] Subject: can I use a /31 subnet to the link between 2 routers eth ports. [7:55450] I used thought it shoul be /30 mask subnet... but recently I saw some guy said: use /31 subnet to save the address.... I really confusing me... ######################################################################## ############# Scanned for Viruses and Content and cleared by the Webvein Mail Gateway ######################################################################## ############# ######################################################################## ############# Scanned for Viruses and Content and cleared by the Webvein Mail Gateway ######################################################################## ############# Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=55479&t=55479 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
