BGP Route flaps, accidental fiber cuts, equipment failure, these are all things that trigger outages and cause traffic to behave erratically and unpredictably. In the moment of crisis, a five minute voice outage feels like an eternity. What many people do not realize is, just when the network begins to “normalize” itself, this will cause [...]
Archive for the ‘SBC’ Category
Acme Packet SBC: SIP Endpoint Registration Behavior During a Network Outage (avoiding SIP overload and registration flooding)
Posted: 21st December 2012 by Mark in Acme Packet, BroadWorks, SBC, SIP0
Acme Packet SBC: Configuring “Selective” Early Media Suppression
Posted: 18th December 2012 by Mark in Acme Packet, BroadWorks, SBC, SIPThe Acme Packet SBC includes support for Early Media Suppression. This allows you to decide what Realms can and cannot support Early Media and in what direction Early Media is allowed. Taking it one step further, the Acme Packet SBC also supports Selective Early Media Suppression. This means that even if a realm is configured [...]
Active Directory based Call Routing on the Acme Packet SBC (Integrating CUCM, Microsoft Lync, and PSTN SIP Trunking)
Posted: 5th October 2012 by Mark in Acme Packet, SBC, SIPMany Enterprises have migrated (or will soon migrate) to SIP Trunking for PSTN access. For an Enterprise with a single IP PBX platform and an SBC on the edge, call routing from the PSTN to the internal network is typically very straight forward because all DID’s point to one IP platform. Example of a simple [...]
Acme Packet SBC: The New “SIP Monitoring and Tracing” Tool for Troubleshooting SIP Calls
Posted: 8th August 2012 by Mark in Acme Packet, SBC, SIPDiagnosing a troubled SIP call has a tendency to be a real pain. Whether it’s running wireshark, tcpdump, or collecting debugs, having to sort through duplicate packets and attempting to merge different pcap files together does not provide a simple way to troubleshoot a single call while looking at both sides of the call in [...]
Acme Packet SBC and “trans-expire” Timers (reducing post-dial delay due to Invite timeout)
Posted: 10th April 2012 by Mark in Acme Packet, SBC, SIPBy default when a SIP Invite is sent from a SIP endpoint to the Acme Packet SBC, the default expires timer is used to determine when the Invite will timeout based on no response. Changing this globally may not produce the desired result as this impacts all Invites to all devices across all realms. In [...]
Acme Packet SBC and the “register-grace-timer” sip-config Option
Posted: 24th January 2012 by Mark in Acme Packet, BroadWorks, SBC, SIPThe Acme Packet SBC contains an optional parameter that may be added to the configuration which helps avoid a SIP avalanche from occurring. One instance of a SIP avalanche is when a very large number of SIP endpoints consecutively send SIP registrations to an SBC which then forwards them to a SIP registrar. This can [...]
In most cases a SIP Redirect Server simply responds to a SIP Invite with a 302 Moved Temp message and provides multiple contacts in the Contact Header. When this occurs, the device receiving the 302 Moved Temp message (such as an Acme Packet SBC) will attempt to contact (ie. send a SIP Invite) the first [...]
Answer to Seizure Ratio-Based Routing on the Acme Packet SBC
Posted: 25th October 2011 by Mark in Acme Packet, SBC, SIPAnswer to Seizure Ratio (ASR) is a term used in Telecommunications and helps determine when new call setup attempt should be routed to an alternate destination. The definition of ASR is the number of successfully answered calls divided by the total number of calls attempted (seizures) multiplied by 100. The formula is (Answer / Seizure) [...]
Acme Packet SBC “packet-trace” Command (capturing SIP signaling)
Posted: 21st October 2011 by Mark in Acme Packet, SBC, SIPThe packet-trace command allows the Acme Packet SBC (Session Director) to capture SIP signaling communication between two endpoints and send the capture to external server such as Wireshark.The SBC uses the network interfaces (ie. media interfaces) to send the capture. The wancom management interface is not supported in this case. The first step is to [...]
The Importance of the “alarm-threshold” Command on the Acme Packet SBC
Posted: 23rd May 2011 by Mark in Acme Packet, SBC, SIPThe alarm-threshold command gives the Acme Packet SBC the ability to send minor, major, or critical alarms when CPU, Memory, Rfactor, Space (/ramdrv), and Session count reach a specific threshold based on % usage. Each element is monitored individually so the alarm is sent only for the violating element. Setting these values is a great [...]