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Voice Over IP

Voice over IP (VoIP) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. Other terms commonly associated with VoIP are IP telephony, Internet telephony, broadband telephony, and broadband phone service. The term specifically refers to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN).  Examples of the VoIP protocols are H.323, Media Gateway Control Protocol (MGCP), Session Initiation Protocol (SIP), H.248 (also known as Media Gateway Control (Megaco)), Real-time Transport Protocol (RTP), Real-time Transport Control Protocol (RTCP), Secure Real-time Transport Protocol (SRTP), Session Description Protocol (SDP), and Inter-Asterisk eXchange (IAX).

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I want a cheap 800 number service. 3 choices with prompts. All I want is voip. There is no call center. No forwarding to cell phones. Maybe just used for voicemail. A free 1 month trial and an expensive bill is expensive.
Hello and Good Morning Everyone,

          I recently added another phone line to my AT&T setup.  The hardware hookups are as follows:  The telephone/copier/fax machine has a direct telephone line connection to the back of the AT&T Gateway at the port labeled Phone Lines 1 & 2.  Then, I have another telephone line running from the Ext port of the  telephone/copier/fax machine  to the chordless phone.  That said, an AT&T agent explained to me that the  telephone/copier/fax machine with the direct connection to the Gateway will get the new activated number and the other phone, chordless one, will retain the old VoIP number.   Given this information, could someone explain what is meant by VoIP or Voice Over IP?  I did not want to bog down my AT&T agent with too many questions.  So, I decided to submit this one for review here.

            Any shared thoughts and explanations in simple terms with respect to the definition and function of VoIP will be greatly appreciated.

            Thank you

Difference between VOIP and SIP.  Could someone give me a practical description of what the main differences between VOIP and SIP are?
This is about the switch infrastructure using Cisco switches. Currently, there is only using one Cisco WS-2960x-48 POE switch. We also using Cisco UCS 500 series for the VOIP. We are using vlan 101 for data, and 102 for voice. Please see the attached cisco switch configuration.

Now, we intend to buy one new Cisco Meraki MS120-24 ports switch, and join this switch into the switch infrastructure. We also intend to add-in 2 more VLANs for our new VMware virtualization management and backup segments. This is a new 2-hosts virtualization (vmware), with 2 network ports to form a trunk carrying existing vlan 101 (data), management (vlan 121), and backup (vlan 122) from each host. How should I update in my existing POE switch and also the new Meraki switch? Can I make all the 3 vlans - 101, 121, and 122 routable but only allow selective ip to access. For example, only allow 192.x.x.25 to access all vlan 121 & 122 only, but not the other way round.

Thanks in advance.
Shoretel and switch STP on/off?


Looking at replacing our switches from procurve to Aruba.   Changing the method from daisy chained via ports to a stacked method using same models.  

Im unsure if we need to have STP disabled for shoretel to function?  If this is the case we cannot stack, which i find odd.

Hello everyone,
We have a ShoreTel VoIP phone system and we would like to use it to page different zones from the ShoreTel desk sets.
We have a 3 zone Valcom Page Control Unit.
Our paging goal is this:
  1. Page outside only
  2. Page inside only
  3. Page outside and inside at the same time
Is there a solution to accomplish these scenarios?
Do we replace our current Valcom 3 zone paging control unit with a new paging control unit capable of accomplishing the 3 scenarios?
What options exist for porting a Google Voice phone number over to other services?

A couple of users who I support are interested in doing this and want to find out what other services they can port (transfer) their existing Google voice phone numbers too.
I have installed Google voice on my Sprint PCS iPhone X.

Now how can I make my Google Voice number replace my Sprint PCS iPhone X caller ID number so that everytime that I call someone my Google Voice (and not my regular Sprint PCS phone number) will display on all outgoing calls?

Where do I go to enable this setting?

I received the email below on June 1, 2018 and I'm not sure how this affects my Sprint PCS Google voice service:

We are contacting you to let you know that per previous communication, due to upcoming upgrades to Sprint’s network, Sprint will no longer be supporting the Google Voice with Sprint integration. Effective today your Google Voice integration with your Sprint phone number (xxx) xxx-xxxx has been disabled by Sprint.

Effective today:
All outgoing calls (including international calls) and texts will be made through Sprint at Sprint’s calling and texting rates, if applicable.
All new messages, calls, and voicemails sent from your Sprint phone will not be stored in Google Voice. You will still be able to see your messages, voicemail, and call history from before June 1, 2018 in Google Voice on your Sprint device. You can also export this data from your Google Voice account at takeout.google.com.
You won’t be able to use Google Voice-enabled capabilities such as call forwarding, voicemail transcription, spam detection, and other Google Voice features. These capabilities can be enabled from your Sprint device. Click here for more information …
I have a remote extension (yealink handset) that is dropping outbound calls after 35 seconds. I have diagnosed through logging that the asterisk server is not receiving the proper ACK, and the reason for that is that the asterisk server is looking for the reply from, which is the local subnet of the remote phone. Obviously the asterisk server will never receive a reply from that address. What changes do I need to make so that the asterisk server is looking for replies from the WAN IP of the remote network? NAT is setup properly on both ends. For reference, this is CompletePBX from Xorcom that we're dealing with and a copy of the asterisk log error is below.

[2018-08-16 09:27:08] WARNING[5720] chan_sip.c: Retransmission timeout reached on transmission 405286438@ for seqno 2 (Critical Response)
I am running the newest version of Skype on my Windows 10 PC.  I need to contact someone (I have their Skype name), but when I try to connect I get the following message:

Skype Error
I don't use Skype often, and tried to find a setting or other evidence of the problem, but can't.  Can you help?


I am converting to SIP at a company site.  I set up the fortigate 60d identical to another one of our company sites where SIP is already implemented.

The SIP Cloud provider tells me that the firewall is not "passing confirmation packets  the phone system (PBX) sends out when it detects an incoming call",
and this is causing their system to transfer the call to our failover number.

I have opened up all requested ports (TCP/UDP etc), configurd policy,and QOS to high priority- everything they suggested, and as I mentioned earlier, it is configured exactly like our other site's fw.

I suspect it is a configuration with one of their servers.  In any case, Logging for all events is enabled in the firewall policy.  How can I tell if the firewall is blocking/not passing back the confirmation packets they SIp provider mentions?
I have a client with allworx phone.  The moron didn't asked what type of speed we are running so we went from 1gb connection to 100mb connections because they connected the PC to the phones. I'm not sure if I have enough IP jacks to move the phone to a separate connection.  I was told there are splitters that will allow 1 gig for the PC.  Does anyone know about what the splitter is and where  can purchase?
Multiforest LDAP Not able to authenticate with remote trusts (Cisco VOIP).

We had to part ways with a vendor that was managing our VOIP system that services multiple school districts. We use a single domain controler for the voip domain that holds trusts to each member district. This allows self service portal and jabber authentication, as well as synchronization of user accounts. Everything LDAP related suddenly stopped working and we were unable to get the current multiforest instance of LDAP to connect to the school districts local domain controller. We were at risk of the voip system removing over 600 accounts, so as quick fix, we configured the Cisco Call Manager , so it connects to each districts LDAP server, directly. This workaround synchronized all user accounts, but the authentication configuration cannot work with our current configuration. We are now looking at the original configuration, in hopes of restoring authentication.

The previous support company had set up the LDAP Manager Distinguished Name as cn=user, cn= multiforest, cn=local, yet the server is not known by that name or domain and ad explorer errs out when attempting to use multiforest.local as the target. We can browse LDAP of the same server with AD Explorer, by IP and can see the trust domains under "users" Domains are appended with $. See screenshot. In short, I need help identifying the proper LDAP Manager DN and search base, so we can restore authentication via our trusts, rather than …
What is the difference between these user licences? I am running CUCM 10.5 with roughly
300 CIPC users and three SIP trunks for inbound calls from a Call Center.

LIC-UCM-10X-ENHP-A      UC Manager-10.x Enh Plus Single User License      CON-ECMU-LICMEHPA
LIC-CUCM-10X-ENH-A      UC Manager-10.x Enhanced Single User License      CON-ECMU-LIC0ENHA
LIC-CUCM-10X-ESS-A      UC Manager-10.x Essential User License User      CON-ECMU-LIC0ESSA

We have our Shoretel HQ server in City A and there are two other sites that are connected to it and all of their associated phone devices.
We are decommissioning the data center in City A so we are trying to find out the best way to migrate the HQ server to City B.
The current IP subnet that it is on cannot be easily migrated due to multiple MPLS networks and dependencies on that subnet in City A.

Is it possible to create a new VM in City B and set up the Shoretel HQ server there with a new IP address? I assume we will need to update the sites and their associated devices with this new IP, but would it require a manual effort or is there a simple way to do this?

This way we can easily decommission the HQ server in City A once we have everything connected to City B.

Has anyone done this before?

When I call my cell phone using skype on my windows 10 computer
I see the caller id that I selected on skype.com
I am spoofing my phone number to display another phone number that I use but am not currently using because I am calling from a computer.

But when I call a big business the number that shows up is not mine and can not be called again.

How do I purchase the caller id system that a big business has.
Caller ID that does not work with a spoofed phone number.
good day,

I have two switch both configured for vlan 869 (Voice). The phones connected to SW01 can get IP address and phones connected to SW02 cannot get IP address. Can someone assist where I made configuration mistake. This is my first config as I am learning the Cisco commands. Attached are my configurations for both switch.
Hi, we have a data network here with Cisco switches that we manage. Now, there is a also a VOIP vendor who his own switches in our network. (He didnt want to use ours and VLAN everything).

Both the networks are on different subnets. Now, we noticed all of a sudden PC's started getting IP's from the phone subnet...and it's wreaking havoc internally. I tried to manually trace all 200+ cables in the office to see if someone plugged a phone device into the data network, but no luck..

How else can i troubleshoot this from say a switch level?
For people that own / manage 800 numbers for businesses:

Do you get charged for / pay for calls from payphones?  Years ago there was a charge - 26c I think it was - that people that own toll free numbers were charged that went to the pay phone owner.  Wonder if that's still in effect. And for bigger businesses, do they (the 800 number supplier) not charge the 800 number owner?

And 800 numbers - does the owner typically pay a per minute cost? Or has it moved like outgoing phone lines to a flat fee / month?

Cisco 8851 phone not detected into the network. When I plug the phone directly into the switch in registers just fine in call network. Back at my work station. I plug the computer into the corresponding port and it works fine. Plug the phone in, and it get PoE just fine, but cann't see the network. I have cleared port-security on the switch. The phone is set to recieve DHCP just fine. The settings seem to be correct as I can plug the phone directly into the switch and the phone registers in Call Manager just fine. Plug it into the corresponding port back at the work station, and no go.
I have a Galaxy Note5 that I use as an auxiliary device.  In other words it does not have a SIM card in it.  It only connects to the internet via Wi-Fi.

I would like to have Google Voice to be the default dialer for this device.  I tried to research this issue a few times but I can't seen to figure it out.

The Note5 is running Android version 7.0
Is there a converter or way to utilize a very nice slightly used Panasonic phone system that does not have VOIP technology built in to the phone system. It's perfect for a small business. Bought it a few years ago as the VOIPs were coming in. Wish I had not now. Unfortunately I have a cell phone but would like to utilize the home phone system NOT VOIP again because its conveniently setup to two different work stations. So I was wondering if the phone system I have can still be utilized with a phone line though some kind of a converter or am I forced to purchase all new phone system that works with VOIP? Because I am under contract with AT&T cellular. I unfortunately cannot switch and AT&T does not have landline services in my area so that means I have to get all new services with another provider? It just mean redundancy I just do not want to put everything through my cell phone. when I have a super nice phone system in house. Your thoughts appreciated.

We have a Skype account for our company.

We sign in with our company email address to access our Skype account on our Windows 10 Pro PC.

For people to get in contact with us, they usually request a Skype ID.

Our Skype ID displays as something like the following: live:" "_(numbers)

We would like to change this as it does not look professional.

How do we change the Skype Name/ID for our Skype account?

We are aware we can change the display name for the account but the Skype ID is needed for people to search for our company on Skype.

I have a DHCP server with two IP scopes.  We also have VOIP phones that use a separate VLan and receives their IP addresses via a DHCP server on my router.  We had some problems with the VOIP Vlan and was forced to put all the phones onto the default DHCP server with my computer devices.  Once we fixed the VLAN issue, we changed the configuration in the phone which put all the phones back on their own VLAN, thus releasing all the IP's leases from my default DHCP server.  This morning, I got a warning that my DHCP server was using 88% of the IP's, looked at the server and all the phones leases were back.  I know these phones are not using these IP's because the change is manual.  Each phone had to be put back onto their VLan through a manual setup.

My lease time is 6 hours, so I deleted all the phone devices that showed up, but does anyone know why after a week, they showed up and started pulling IPs?

when I call Santander bank using skype
"welcome to skytel system"

but I can call using a cell phone

Please explain why you think I am blocked

Voice Over IP

Voice over IP (VoIP) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. Other terms commonly associated with VoIP are IP telephony, Internet telephony, broadband telephony, and broadband phone service. The term specifically refers to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN).  Examples of the VoIP protocols are H.323, Media Gateway Control Protocol (MGCP), Session Initiation Protocol (SIP), H.248 (also known as Media Gateway Control (Megaco)), Real-time Transport Protocol (RTP), Real-time Transport Control Protocol (RTCP), Secure Real-time Transport Protocol (SRTP), Session Description Protocol (SDP), and Inter-Asterisk eXchange (IAX).