On 26.01.2009, at 12:05, Benny Prijono wrote: > On Fri, Jan 23, 2009 at 5:14 PM, Ruud Klaver <ruud at ag-projects.com> > wrote: > > On 23 Jan 2009, at 01:19, Alexei Kuznetsov wrote: > > Hi, > > There's a problem on the Mac OS X with installed Parallels, which > adds virtual nics to the host machine. pjsua-lib bounds to one of > these addresses and tries to use it in signalling and media. I know > I can use bound_addr explicitly, but it's not the point. I'd like to > predict the way my app bounds to the local addresses and do > something to make it more convinient for the user. So, is there any > algorithm? > > > I have also noticed this problem. It seem to be pretty random, but > I'm curious to know if there is any logic behind it. > > > Of course there is! Do you think pjsip just subjectively selects IP > interface at random? It's not that clever you know. ;-) > > Here: > http://trac.pjsip.org/repos/browser/pjproject/trunk/pjlib/src/pj/sock_common.c#L448 > > The selected IP shouldn't matter much IMO. For signaling, the IP > will be (re)learnt from REGISTER response. And for media, that > exactly what ICE is for, among other things. > > cheers > Benny Yes, that doesn't matter much in general case. But I have a user whose SIP provider uses Communigate Pro, which tries to solve the NAT problem by routing media through itself and not using STUN. It does not support ICE either. This behaviour depends on the appropriate published IP address of the SIP user agent. As far as I understood the code from sock_common.c, the user's machine chooses the address here /* If we end up with 127.0.0.0/8 or 0.0.0.0/8, resolve the IP * by getting the default interface to connect to some public host. * The 0.0.0.0/8 is a special IP class that doesn't seem to be * practically useful for our purpose. */ if (status != PJ_SUCCESS || !pj_sockaddr_has_addr(addr) || (af==PJ_AF_INET && (pj_ntohl(addr- >ipv4.sin_addr.s_addr)>>24)==127) || (af==PJ_AF_INET && (pj_ntohl(addr->ipv4.sin_addr.s_addr)>>24)==0)) { status = pj_getdefaultipinterface(af, addr); } because computer's hostname does not resolve and the first available interface is the interface that we'd like to be default (but it's not). Here's an example. 10.211.55.2 is chosen as a default by pjsua-lib. User's default router is 192.168.1.1. lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384 inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1 inet 127.0.0.1 netmask 0xff000000 inet6 ::1 prefixlen 128 inet6 fd92:a3:1186:7c97:21e:c2ff:fe1b:26d7 prefixlen 128 gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280 stf0: flags=0<> mtu 1280 en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500 ether 00:1e:c2:1b:26:d7 media: autoselect status: inactive supported media: autoselect 10baseT/UTP <half-duplex> 10baseT/UTP <full-duplex> 10baseT/UTP <full-duplex,hw-loopback> 10baseT/UTP <full- duplex,flow-control> 100baseTX <half-duplex> 100baseTX <full-duplex> 100baseTX <full-duplex,hw-loopback> 100baseTX <full-duplex,flow- control> 1000baseT <full-duplex> 1000baseT <full-duplex,hw-loopback> 1000baseT <full-duplex,flow-control> none fw0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 4078 lladdr 00:1f:5b:ff:fe:10:b7:c4 media: autoselect <full-duplex> status: inactive supported media: autoselect <full-duplex> en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500 inet6 fe80::21e:c2ff:febb:c8fc%en1 prefixlen 64 scopeid 0x6 inet 192.168.1.34 netmask 0xffffff00 broadcast 192.168.1.255 ether 00:1e:c2:bb:c8:fc media: autoselect status: active supported media: autoselect en2: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500 inet6 fe80::21c:42ff:fe00:8%en2 prefixlen 64 scopeid 0x7 inet 10.211.55.2 netmask 0xffffff00 broadcast 10.211.55.255 ether 00:1c:42:00:00:08 media: autoselect status: active supported media: autoselect en3: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500 inet6 fe80::21c:42ff:fe00:9%en3 prefixlen 64 scopeid 0x8 inet 10.37.129.2 netmask 0xffffff00 broadcast 10.37.129.255 ether 00:1c:42:00:00:09 media: autoselect status: active supported media: autoselect Any thoughts? Alexei
