Inbound UDP 137 traffic keeps appearing

Unanswered Question
Apr 27th, 2008
User Badges:

I have a ASA 5510 configured with vpn capability. Somehow the vpn client will keep broadcasting the traffic via UDP port 137. Why is this so?


Thanks



  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Richard Burts Tue, 04/29/2008 - 04:30
User Badges:
  • Super Silver, 17500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

Leonard


Broadcasting on UDP port 137 is a typical Windows networking behavior. Are these VPN clients Windows PCs?


HTH


Rick

Richard Burts Tue, 04/29/2008 - 04:46
User Badges:
  • Super Silver, 17500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

Leonard


Because if they are Windows PCs then broadcasting on UDP 137 is a normal behavior. Your question suggested that there was something unexpected or unusual. But Windows PCs broadcasting on UDP 137 is quite normal.


HTH


Rick

leo_zidane Tue, 04/29/2008 - 04:50
User Badges:

However the ASA 5510 keeps sending me alerts on the VPN clients keep broadcasting the traffic indicating them to be critical alerts. Why is this so?

Richard Burts Tue, 04/29/2008 - 07:20
User Badges:
  • Super Silver, 17500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

Leonard


Without knowing how your ASA is set up I could not tell you why it is alerting on this traffic.


HTH


Rick

leo_zidane Wed, 04/30/2008 - 04:44
User Badges:

Thanks. I don't remember setting my firewall on this setting. But from your expertise what can the problem be isolated at?


But then my VPN permit client out to the internet after they are authenicated. Cannot be they must keep broadcasting the network with netbios.

Actions

This Discussion