To the sales team, I sound like a broken record as I repeated the engineering driven mantra: “A VoIP solution is only as good as the network it is build on”.     No matter how many times we tell clients that you can not obtain reliable, predictable toll quality voice communications over the public Internet, they insist on having us implement it.   The old marketing adage “you do not give customers what they need, you give them what they want” clearly [...]

This is a follow up post to an earlier post on LLDP-MED. VoIP phones on the market today follow the same basic boot and operations process: 1 – Wait for an LLDP packet from the Ethernet switch 2- Send a DHCP discovery packet to find the DHCP Server 3- Send a DHCP request to the DHCP server to get an IP address 4- Send an LLDP-MED packet to the Ethernet switch 5- Wait for an LLDP-MED packet from the Ethernet [...]

If you are and iPhone aficionado, you absolutely want your iPhone to work  on your ShoreTel IPBX! I recently downloaded VeNetCorps SipPhone fromt the iPhone App store! There are several SIP phone apps at the store, but most have a pre-programmed domain name for the sip registration proxy server. If you want to use your own SIP proxy there was no easy way to change the IP address so you had to hack your DNS to get it to point [...]

When VoIP gateways first started hitting the market back in 98′, the vendors tried to packetize DTMF and quickly learned it did not work well.   For this reason they quickly learned to “regenerate” DTMF at the outbound gateway rather than packetize and truck it across the network.   Moving modem tones is even more challenging and most VoIP solutions discourage attempting to send modem tones over an IP connection.  If you can get it to work at all, the modems will [...]

In telephony, IP QOS is somewhere between a science and an art. Setting up VOIP QOS on your network is essential for toll quality voice from end point to end point, especially across a WAN. Historically, in ShoreTel, IP packets were marked with the DSCP value set in the Call Control Options page. Generally this is generally set as a value of 184 or Precedence Level 5, what CISCO would call Express Forwarding or EF. This value is represented as [...]