The Official Wireshark Blog

We are here at www.wireshark.org…

Categories: Infrastructure
…where we’ve secretly replaced the Internet Explorer we usually serve with Chrome Frame. Enjoy.

Polycom IP Phone Boot Analysis

Categories: Analysis
Tags: ftp voip

We use Polycom SoundPoint IP phones here at the CACE Technologies World Domination Secret Lair. While troubleshooting a different problem recently I noticed that the phones do something funny. During the boot process they obtain an IP address via DHCP, similar to most PCs. A DHCP option tells the phones to fetch their configuration and firmware from an FTP server. The funny part is that some of the FTP transfers were failing even though the phones booted up just fine:

SIP firmware download failure

SIP firmware download failure

At packet 175 the phone starts to download sip.ld, the SIP firmware image. The transfer starts at packet 177, but the phone cuts the transfer short at packet 181. The phone then behaves as if nothing is wrong. What’s going on here?

Wireshark’s Welcome Screen

Categories: Tip

Wireshark 1.2 added a nifty welcome screen which lets you start capturing, load a capture file, get help, and lots of other things. At the very top of the screen we brag about our popularity.

You can change that message to anything you like.

🔗