nanog mailing list archives
Re: Using /31 for router links
From: Jay Nugent <jjn () nuge com>
Date: Fri, 22 Jan 2010 19:31:30 -0500 (EST)
Greetings, On Fri, 22 Jan 2010, Seth Mattinen wrote:
In the past I've always used /30's for PTP connection subnets out of old habit (i.e. Ethernet that won't take unnumbered) but now I'm considering switching to /31's in order to stretch my IPv4 space further. Has anyone else does this? Good? Bad? Based on the bit of testing I've done this shouldn't be a problem since it's only between routers.
Yes, this *IS* done *ALL* the time. P-t-P means that there are ONLY two devices on the wire - hence point to point. It ONLY uses two IP addresses (one on each end) and there is no reason or need to ARP on this wire. So no need for a broadcast or network addresses - it is just the two end points. --- Jay Nugent Nugent Telecommunications Train how you will Operate, and you will Operate how you were Trained. +------------------------------------------------------------------------+ | Jay Nugent jjn () nuge com (734)484-5105 (734)649-0850/Cell | | Nugent Telecommunications [www.nuge.com] | | Internet Consulting/Linux SysAdmin/Engineering & Design/ISP Reseller | | ISP Monitoring [www.ispmonitor.org] ISP & Modem Performance Monitoring | | Web-Pegasus [www.webpegasus.com] Web Hosting/DNS Hosting/Shell Accts| +------------------------------------------------------------------------+ 7:01pm up 43 days, 18:42, 3 users, load average: 1.10, 0.96, 0.63
Current thread:
- Using /31 for router links Seth Mattinen (Jan 22)
- Re: Using /31 for router links Jay Nugent (Jan 22)
- Re: Using /31 for router links Nathan Ward (Jan 22)
- RE: Using /31 for router links George Bonser (Jan 22)
- Re: Using /31 for router links Nathan Ward (Jan 22)
- Re: Using /31 for router links Joe Provo (Jan 22)
- Re: Using /31 for router links Seth Mattinen (Jan 22)
- Re: Using /31 for router links Chris Costa (Jan 22)
- Re: Using /31 for router links Jens Link (Jan 23)
- RE: Using /31 for router links Erik L (Jan 22)
- Re: Using /31 for router links Seth Mattinen (Jan 22)
- Re: Using /31 for router links kris foster (Jan 22)
- Re: Using /31 for router links Richard A Steenbergen (Jan 22)
- Re: Using /31 for router links Jay Nugent (Jan 22)
- Re: Using /31 for router links Tony Varriale (Jan 22)