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For questions about Voice over Internet Protocol (VoIP) which encompasses various technologies (methods, functions, and encapsulations) for encoding and delivering audio on a network using IP.

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2answers
30 views

Advice on potentially needed subnet expansions

I work for a non-profit with some slightly more antiquated hardware. We have 3 locations, about 700 devices across them. Right now our locations are set up as: Location 1 (Main) - /23 with a DHCP ...
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0answers
11 views

VoIP RTP feedback/echo - RTP voice stream from remote caller is amplified and reflected back to them

I have a specific issue where calls start to deteriorate after about 20 seconds, then usually get progressively worse. I'm looking for help in narrowing down the cause. The deployment is a cloud PBX, ...
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1answer
43 views

How Does Making a VoIP call through PSTN Work? [on hold]

for my college work i was told to draw a diagram showing "information flow" of someone making a VoIP call through PSTN and then explain how it works. After doing research for the last 3h hours stuck ...
2
votes
0answers
21 views

Cisco phone display name change

I am trying to change name on cisco ip phone 7942. I changed the name in directory number configuration and in phone configuration of phone on CUCM. I did reset of phone too. But still showing the old ...
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0answers
30 views

QOS - the need for it and verifying it

Just some straightforward questions, hope gurus here can shed some light 1) show int - output queue -> this is the hardware queue (tx-ring) or this is the software queue ? if I see drop, this means ...
1
vote
1answer
22 views

Cisco Unity Connection guest, ESXi host, IP phones, vlan, subnet, ip addresses, qos

I have setup: VLAN 1 and subnet 192.168.1.0/24 for data VLAN 100 and subnet 192.168.100.0/24 for voice IP phones get their IP via DHCP on the subnet 192.168.100.0/24 all other IP devices get their IP ...
1
vote
1answer
34 views

Cisco 3750 - configure to mimic multi location scenario

Good morning. For starters, I am less than a noob with cisco products. I can access, so basic trunking for our nec phone systems, etc. I have a 3750 that I'd like to configure to mimic a multi ...
6
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3answers
617 views

Is QoS an issue for VOIP calls over the Internet? If not, why not?

I'm trying to decide whether I should buy SIP trunks from my ISP or a 3rd-party. As I understand it, it's important to maintain QoS on an internal network (i.e. prioritize VOIP traffic). Is this not ...
4
votes
1answer
64 views

VOIP timeout behind Cisco ASA after Duplicate ACK and Retransmissions

We have a RingCentral Polycom VVX series VOIP phone behind a Cisco ASA 5506 that will provision, work for about five minutes, go off-line for 20 minutes then reconnect and continue to work unless ...
4
votes
1answer
99 views

What Is Session Border Controller [closed]

What is Session Border Controller(SBC). And What is the Advantages of SBC. How Does It Works?
2
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3answers
98 views

Cisco Vlan block access

So I have 2 core switches and 1 access switch, I have the vlans 1, 10, 20, 30 and 100. Vlan 10 is voip and what I would like to do is stop anyone on the other vlans from being able to see that subnet, ...
1
vote
1answer
150 views

1-1 NAT on a SonicWall with a DMZ

A new PBX is being installed at one of our clients today, and they have requested that we give them one of our unused public IP addresses(Comcast is the ISP, have a block of IPs) for use with the PBX. ...
3
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0answers
31 views

Configure C1861 for SIP to FXS port

I found a C1861 ISR router and I would like to play with it a learn some telephony. I signed up for a VOIP service so I have SIP credentials. Is there a simple walkthrough anywhere to set up the SIP ...
0
votes
1answer
394 views

Fortigate 90D SD-WAN: VPN and VoIP

i am contemplating the idea of switching our current FG 80D to a 90D and implement SD-WAN using our current 100Mbit fiber circuit (main) and the 4G LTE (cradlepoint) for internet backup. Our current ...
1
vote
1answer
326 views

Problems Adding IPPhone to VLAN in Packet Tracer

I am trying to add two IPPHONES in a VLAN and it does not seem to be working as the phones are not receiving their ip addresses. I have a router going through a switch and the phones are then ...
1
vote
1answer
130 views

Phone and PC network sharing one wifi bridge

We have a Cisco router from our T-mobile provider, two subnets on two ethernet ports: one subnet for PC data network, one subnet for IP phone network. The subnets have different IP addressing. As per ...
0
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0answers
35 views

SIP registration not converting to 'Yes' in VoIP configuration

I am trying to configure VoIP phone which is of grandstream GPX-1625. I have successfully set and configured the IP address in it, but the issue is SIP registration is not converting to "YES".I am ...
3
votes
2answers
158 views

VLAN Tags Being Different for a VoIP Phone vs. the Host Daisy-Chained to it?

I've recently began working for a VoIP Provider and I am constantly seeing VoIP Phones pulling different VLANs than the Host that is connected to it i.e. daisy-chained. When I've tried to look more ...
0
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1answer
57 views

Is there a point to have VLANs if each PC client can access them all?

At work we have a config where VLAN 1 is the main network and VLAN 2 is the phone system. The workstations connect automatically to VLAN 1 but can also access the control panels of each phone through ...
3
votes
1answer
289 views

EX3300: Voice VLAN stopped working after upgrade to 15.1R6.7

We have 50+ Juniper EX3300 switches with access points configured to work with dot1x and voice vlan. We also have a variety of Yealink T23G, T42G, T26G and T48G phones that worked perfectly in our ...
6
votes
1answer
1k views

Do i need to configure VLANS on my router/firewall or just the switch?

I finally took time to map my entire shitty network to understand exactly what the guy before me did, and i must admit i'm a little bit surprised even if i'm not a network expert... Just take a look ...
0
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1answer
157 views

Cisco 7960 SIP phone background image issues

I have an asterisk home PBX and I recently got a Cisco 7960G on eBay. So far I got everything working but the background images are quite tricky. I followed one short how-to and I was able to actually ...
1
vote
1answer
186 views

QoS implementation for VoIP network

We are in VoIP business and running RTP/SIP traffic 80% in our network we have other servers also like www and monitoring and operation, our network is very flat and simple also we have very basic ...
1
vote
1answer
91 views

Configure switch in GNS3

Is there any way to configure a switch in GNS3?
0
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3answers
193 views

Can I run two separate internet connections over one Cat5e cable

I have two ISP's coming into the building. One is a T1 that is going to be used for VOIP phones. The second is high speed internet connection going to be used for internet. Each office has one cat5e ...
0
votes
1answer
445 views

Bandwidth regulation without QoS and VLAN [closed]

Does anyone know any possibility to do Bandwidth reservation or something equal to it. Mainly to give VoIP and IPTV Bandwidth before the Internet when there is no possibility to use QoS and VLAN. It ...
1
vote
1answer
2k views

Cisco ASA SIP/RTP inspection question

I have following scenario: [VoIP phone]--------[ASA 5550]----------[SIP Server] VoIP phone: 10.0.0.10 SIP server: Public Address Question: In above scenario do i need to specify or open RTP ...
1
vote
2answers
75 views

VoIP only for two phones

I would like to connect only two IP phones to talk each other (I have no idea about IP telephony). Is it possible without using a PBX? I mean, just connecting IP phone to IP phone with a straight/...
0
votes
1answer
176 views

Does UDP work for Load Balancing?

while I was working today on router, My senior said that since VoIP protocol works on UDP, it doesn't support load balancing, which I couldn't quite understand. Can someone enlighten me on this. We ...
1
vote
2answers
84 views

Mostly wireless campus vs. VoIP

We will be replacing our campus network in the next year or two, and we are leaning towards increasing the use of wireless since most people primarily work from laptops & mobile devices. Plus, we ...
1
vote
1answer
187 views

VoIP on a remote VPN site

I have a remote site that needs both data and voice. We have a VPN L2L tunnel up and running back to the hospital, no problem. The concern is that I have data and voice on the same VLAN, and it is ...
3
votes
1answer
283 views

Call is disconnected after huntstopped to another phone

We've been having an issue at the office with our Cisco CME. Here's the situation. Phone A (outside line) dials into the main line and after ~three rings the call is huntstopped to four other phones. ...
1
vote
2answers
170 views

How do I diagnose a VoIP issue on a Cisco 2811?

Background Our shop consists of approximately 10~12 Cisco IP phones which then connect to their respective workstations. Each phone is connected to the only switch in the shop which is a Cisco 2950 ...
1
vote
1answer
44 views

Smart switching calls in a company phone calls

We use VoIP phones in our company. Some people calls and each one connected to first free operator, and each people calls us once a week, we need one more option to make better experience for our ...
0
votes
1answer
43 views

VoIP Provider and Phone Number Routing Questions

I am fairly familiar with VoIP and I have my own VoIP PBX, and my provider is Twilio (for Voice) and CallCentric (for Fax). But How do providers like Twilio work exactly? More specifically: How do ...
1
vote
1answer
190 views

ESI PBX LAN-only VoIP phone forwarding thru IPSec tunnel - remote router sees packets but not phone, doesn't forward

Okay, so we have an older X-Class ESI PBX system, an ESI IVX 128x FSIII [see below for link]. We have an LNC card installed in it, which allows for the use of up to 12 LAN-only VoIP phones. We have an ...
0
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1answer
251 views

Is it possible for ISPs to block part of VPN traffic, like UDP traffic only [closed]

My Question isn't about any carrier or ISP, as it might sound. It's about the technical aspect of internet censorship and needs networking experts to help. As you may know, some countries are blocking ...
0
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2answers
317 views

how to run multiple IP addresses to be allocated off a single Ethernet port. VoIP

Implementing hosted VoIP with connection of desk handset to Apple Macs. Gbit to desktop Cat5, Aruba 2920 PoE J9836 Layer 3 Switch. Line will be separate 10Mb, separate router too. Question: How can ...
0
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1answer
455 views

Real IP phone in GNS3 Problem

I am trying to link this configuration to a real SPA 303 IP phone but I do not know where to begin with this. I have the physical IP Phone, but I want to run it through the simulated environment that ...
3
votes
1answer
805 views

Call incoming from PSTN does not forward to cellphone number

We have a Cisco 2921 connected to an T1 ISDN PRI with Call Manager Express. We are using CP8861 SIP phones. Everything works fine, calling in and out. To better illustrate the problem here's an ...
0
votes
1answer
527 views

How to use a layer 3 switch for QOS between gateway and hosts?

In the following scenario, is it possible to prioritize VOIP/RTP from x.x.x.51 through the gateway with a Cisco switch, and how? I need to prevent x.x.x.50 from saturating the WAN connection. ...
1
vote
1answer
433 views

How does “dual-line” feature work on Cisco/Avaya IP phones for VOIP?

For below CME configuration which I configured on UC500 where ephones are not configured with dual-line feature and in button command separator 'c'(call waiting) is used. CME_VOICE(config)#ephone-dn ...
0
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2answers
451 views

Convert encrypted SRTP to RTP for private network

Let's say that Alice would like to make SIP call to Bob. Alice initiates the call using her mobile device over a cellular network. On the other hand, Bob sits in a local network of an organisation. ...
0
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0answers
2k views

RTP Port Number

Hi, In the screenshot UDP Source Port for RTP is 8000 and Destination Port is 40376. Standard port Numbers for RTP are 16384-32767. Even if we change the standard port range, should it not be min. ...
0
votes
1answer
829 views

Why and when do we use digit '9' before making an outbound call?

Also explain when do we use this feature (Please explain for both VOIP & Traditional telephony system)? Why we use this feature? what problems shall we face if we don't use '9' before making ...
2
votes
1answer
2k views

Difference between sip proxy and sip outbound proxy? [closed]

What is the basic difference between a sip proxy and a sip outbound proxy. Can sip proxy and outbound proxy be the same?
1
vote
2answers
236 views

Splitting Data and Voice by creating GRE tunnel for Data, using overhead for Voice

A client: 3 sites with L2 links to our Data Centre. I create L3 links by providing IP's both sides. I want to create a GRE tunnel over each link with seperate IPs in order to route Data over these new ...
0
votes
1answer
102 views

Auto-Attendant on Cisco CUC

I'm trying to apply an auto-attendant on a CUC, where the voice message will be just played for one time and stops, and if the caller didn't dial anything the call would hangup after 10 sec. I know ...
0
votes
0answers
60 views

Spectralink 8440 doesn't answer an intercom call

Recently got the new Spectralink 8440 phone and it doesn't answer when I page it (it shows the incoming call) Rest of the phones (Cisco SPA514G) are working fine. Intercom extension: 111 My ...
0
votes
2answers
818 views

CISCO CUBE is as SBC suitable for ISP

I am currently planning a voice network and test different ways. Currently a classic IP network with various Cisco Routers is used to bound different media (fiber, copper, MPLS) and route to a classic ...