Voice over Internet Protocol (Voice over IP, VoIP) is one of a family of internet technologies, communication protocols, and transmission technologies for delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.

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16
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4answers
328 views

What alternatives do I have for telephony if my LEC says the Central Office has an issue?

In our New York office we've been waiting for almost a month for Verizon Business to repair a problem at our local CO. They keep saying that the damage from Hurricane Sandy was so extensive that they ...
14
votes
2answers
936 views

Can anybody explain why to use Asterisk PBX rather than standard PBX from Matrix or Siemens [closed]

Can anybody explain why open-source Asterisk is favourable in comparison with a traditional PBX system from a vendor such as NEC/Syntel/Matrix or Siemens.
11
votes
6answers
20k views

Finding cause of TCP retransmission within a LAN

Hello denizens of Server Fault I have an irritating problem with a LAN of about 100 computers, 2 Windows domain servers, and 12 VoIP phones. Since their installation around a year ago, every week or ...
10
votes
16answers
5k views

What service do you use for music on hold?

This may not be a sysadmin question for some, but it is definitely a hurdle I have to jump as the sysadmin for my company. We recently rolled-out a company wide VoiP system (Switchvox, to be exact) ...
10
votes
3answers
375 views

Architecting network with 10 Mbps half duplex phone system

Current Configuration The diagram below shows our current network architecture. All connections are running at 100 Mbps full duplex with the exception of the TalkSwitch phone systems which run at 10 ...
9
votes
2answers
2k views

Can you please explain the difference between PBX and soft switch in less technical terms?

Asterisk is an open source PBX and FreeSWITCH is an open source soft switch. Source: http://www.freeswitch.org/node/117 Can you please explain the difference between PBX and soft switch in less ...
9
votes
2answers
640 views

Asterisk for Small Business - Where to Start?

I have been in IT for a long time now doing software development and some system/server administration, but all mostly software-related services. I would like to help set up a small business (~50 ...
7
votes
4answers
1k views

Cooling requirements for POE switches?

Is there any difference between POE switches and normal switches when budgeting for cooling capacity for a network closet? Normally, when I'm thinking about cooling; I can look at the power draw of a ...
7
votes
4answers
1k views

Asterisk running on VMware

Does anybody have experience or running Asterisk on VMware(?) - specifically the latest ESX...? I've got a proof of concept working but am reticent to roll it out without a bit more reassurance! I ...
7
votes
3answers
418 views

What are some potential uses of Asterisk (PBX) for a “power user”

So I read a lot of good things about Asterisk. I am not however looking to run a call center or small business setup. I am still interested what potential uses it has for me as a "power user" and ...
7
votes
5answers
755 views

Cross-platform VOIP + IM client and Linux server

Right now, a group of our employees is using Skype for group chats and conference calls. They're not using telephone numbers, just Skype user accounts. I'd like to set up a server that will provide ...
6
votes
4answers
2k views

Is it possible or advisable to virtualize a PBX system? How would one go about this?

I'm totally new to the world of VoIP and we are looking to move from our current provider to a solution we host ourselves, mainly because the current service is so unreliable. Unfortunately I know ...
6
votes
3answers
9k views

How many resources does a mumble server need?

Given a default instance of Ubuntu Server LTS, how many additional resources are needed to run a Mumble server ("murmor") for say 10 connected users? I'm curious about: CPU consumption RAM working ...
6
votes
4answers
516 views

VoIP PBX, custom build or appliance?

I'm looking for advices regarding VoIP products. I need to build an in-house VoIP PBX for one of my company's office, and while I'm fairly sure we will go with Asterisk (still leaving the door open to ...
5
votes
2answers
379 views

Is it possible for Wireshark to drop packets purposely?

I would like to test something like VoIP. I would like to test with some "artificial packet loss". Is Wireshark able to do this? Or is there any good solutions?
5
votes
2answers
998 views

How should I structure a VoIP phone system?

I'm going to be setting up VoIP for a small business that is expected to grow rapidly. I don't really understand much about VoIP other than it's a telephone system that works over a regular network ...
5
votes
3answers
166 views

VoIP phone recommendation with good speakerphone under $300 [closed]

I'm looking for about a dozen VoIP phones for a small office. Criteria: Not Polycom (terrible support) Under $300 USD Good speakerphone quality Any brands/models you would recommend based on your ...
5
votes
2answers
1k views

Ways to monitor SIP termination on an asterisk server

I have a nagios setup which ensures that SIP is responsive on my Asterisk server, that's straight forward. My question is, what kind of possibilities are there that the Asterisk server can actually ...
5
votes
2answers
93 views

Trans-atlantic VOIP

We're a Canadian business on the east coast and will soon be opening up a new call centre in Australia. This new call centre will be handling our graveyard shift and will be overlapping with the ...
4
votes
6answers
1k views

Cisco vs Everything else

A huge debate raged when we were setting up a new phone system. The guys doing the install did not believe in paying high prices for Cisco gear when they could do the same things with lower priced ...
4
votes
4answers
592 views

What does “non-IP” originated traffic mean in a TOS?

I am looking at VoIP providers and many of them have a part of their TOS that says they don't allow "non-IP originated traffic." Excerpt from TOS: You shall only send to [DELETED COMPANY NAME] ...
4
votes
2answers
95 views

Using an extension to block a caller

I have a couple of SIP phones and use callcentric. I get a lot of junk calls. I'd like to implement the following feature and would like some suggestions on how to do this: Once I get a junk call, I ...
4
votes
8answers
8k views

How can I simulate a modem over a VOIP connection?

I have a hardware device I need a server to dial into at regular intervals. The problem is I no longer have a POTS line or a modem in any of development computers, and all my production servers are ...
4
votes
2answers
599 views

What would cause a PBX or SIP phone to not register on the network when using Netgear Switches?

We have 3 different types of switches in our network. All of our IP Phones are running on HP 2520-24 PoE switches. Our primary backbone is "supposed to be" running on Netgear GS748T switches. ...
4
votes
3answers
4k views

Bringing people into an Asterisk conference call

I'm using Asterisk 1.4 and am trying to work out a way to bring people into a conference call. In the ideal scenario two people would be talking and one of them would push some keys, then a phone ...
3
votes
5answers
574 views

What are the best LAN communication systems? [closed]

What are the best messaging and VOIP systems for medium to large corporate networks? What have you found to be the best in your experience and why? It should support: Instant messaging Video and ...
3
votes
6answers
1k views

What bandwidth would be required for 55 VOIP Lines And what type of Internet connection

In a call centre environment, what bandwidth would be required for 55 lines? This would be on SIP protocol, would we be best to use G729 codec as i know that our sip provider supports this? What type ...
3
votes
4answers
357 views

Using the Built in Switch in IP phones

I'm working on setting up a small business with IP Phones to connect to the Asterisk Server. Now, for simplicity we just ran 2 CAT5e lines to each room, and 1 was hooked to a phone jack, before my ...
3
votes
5answers
3k views

Running a Vonage router behind a Linksys Firewall

I have a Vonage router used for outgoing VOIP calls. It gets a LAN ip by connecting to a Linksys WRT54g via DHCP. From there, it cannot actually get a WAN ip or connect out. What do I need to port ...
3
votes
2answers
680 views

Extremely Poor VOIP Audio Playback Performance During Live Phone Calls with Remote Desktop Services

The setup: Plantronics USB CS50 Headset > USB Port of "Thin Client" (Running Win Pro) > (Wireless) RDP to Remote Desktop Server > Eyebeam Softphone Client > VOIP Server > Caller (cell phone or ...
3
votes
2answers
2k views

DHCP and DNS services configuration for VOIP system, windows domain, etc

My company has numerous physical offices (for purposes of this discussion, 15 buildings). Some of them are well-connected to our primary data center via fiber. Others will be connected to the data ...
3
votes
2answers
331 views

Using Windows Server 2003's DHCP service to give different router to specific hosts

I have a very small network of maybe two dozen machines, to which I've just added 7 IP telephones, talking to a Mitel controller on another site. I also have 2 ADSL links, using consumer ADSL routers. ...
3
votes
3answers
472 views

Any good phone system on a Windows Environment?

I am looking for a phone system that integrate well with an (almost) 100% Microsoft environment. I would like something that can integrate with Exchange and Active Directory (in-phone ...
3
votes
1answer
164 views

Asterisk: Got 2 PSTN numbers, want to go IP. Need a card

I'm familiar with Networking, VoIP, Asterisk and Linux... but I've never deployed a VoIP with PSTN. I've got one week to deploy VoIP + 2 PSTN numbers, I don't mind reading like crazy but I would like ...
3
votes
1answer
5k views

What is mumbles average monthly bandwidth usage?

I am wondering how much bandwidth does a Mumble server use in the span on a month. I have a dedicated Linux server with 10,000GB bandwidth/month. In their FAQ they have this formula and information. ...
3
votes
1answer
140 views

Does anyone know a good Website comparing all the PBX/IP telephone solutions?

I'm looking for a good website dressing a comparative analysis of the most popular telephony solutions resellers (Cisco, Avaya, Siemens, Microsoft, etc...). I already found a very nice work comparing ...
3
votes
3answers
240 views

Cheap VoIP Phone Recommendation [closed]

I'm looking for an inexpensive corded VoIP phone for my home office that supports SIP. I've been using an old Cisco 7905G with SIP firmware but I'm concerned about security considering that it's ...
3
votes
2answers
2k views

Setting up a SIP NAT proxy

We currently run a VoIP server using an upstream providers SIP proxy for our clients who are behind NAT. We now have the problem that we re ending the relationship with the upstream provider, and will ...
3
votes
2answers
157 views

Looking for ballpark pricing on an affordable a Cisco VOIP solution for our office [closed]

We have about 8 incoming PSTN lines that are currently on an old and antiquated Nortel Meridian ICS system. This system has been giving us some grief. We're looking for a new VOIP solution. I've been ...
3
votes
4answers
8k views

How to stop registration attempts on Asterisk

The main question: My Asterisk logs are littered with messages like these: [2012-05-29 15:53:49] NOTICE[5578] chan_sip.c: Registration from '<sip:912@xx.xx.xx.xx>' failed for '37.75.210.177' - ...
3
votes
2answers
239 views

Dumping configuration from a Sipura 8800

Is there any way to retrieve the configuration from a Cisco Sipura 8800? And no, I'm not talking about nonsense like saving the HTML pages. I'm talking about saving the proper .xml configurations so ...
2
votes
4answers
312 views

Intercom over IP?

This is an odd request, but I'm hoping some of you have had to field it before: We have an office in New York and remote employees in Oregon and Florida. Communication is extremely important to us, ...
2
votes
5answers
193 views

VOIP Power outage strategy

In the past 2 years, we have had 4 instances where we have been without power for a period of 4-6 hours - due to construction crews cutting power lines, car accidents involving downed power lines, ...
2
votes
3answers
345 views

VoIP: converged or not

We are currently looking at VoIP for about 70 users. We're getting a bit confused regarding the choice to run a 'converged' network (VoIP running on the same cables and switches as data) versus ...
2
votes
4answers
206 views

Looking for VOIP hardphone suggestions [closed]

I recently had a couple of Grandstream GXP2000 fail on me, and I am looking to replace them with something (hopefully) a little heartier. I don't need anything too fancy, but the replacement should ...
2
votes
3answers
523 views

Costs For Building An In-House Custom VoIP Gateway?

I am looking for both technical and financial advice for this. In short, my client has approached me concerning a project that they wish to undertake regarding building a very small "today" call ...
2
votes
5answers
2k views

Unable to call through asterisk

I want to create a voip service.I have installed asterisk-1.4 on a dedicated remotely hosted debian lenny distro. I made a sip.conf and extensions.conf so as to place a call between two sip phones(i ...
2
votes
3answers
4k views

Simple Voip server for ubuntu

I have a network that connects 2 households and would like to setup a simple voip server so that I can call between the houses. It needs to be for ubnutu , I have used the free 3CX system and while ...
2
votes
2answers
325 views

VOIP Codec Preference

Do any of you have a preferred codec for VOIP traffic? I guess this is another case where the answer varies depending on use case, equipment, topology, etc... I'm trying to find an optimal codec to ...
2
votes
5answers
855 views

VOIP and IM communication without a server

Typical enterprise VOIP solutions like MS Comm Server require a server computer to handle communications. Is there any program that can do it Peer-2-Peer (P2P) without a server, and directly call and ...