9
votes
Accepted
Is QoS an issue for VOIP calls over the Internet? If not, why not?
VoIP over the public Internet can be a problem, but it usually works good enough, most of the time, although there can be times where it sucks. Most ISPs have extra cost features where they will honor ...
- 101k
8
votes
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.
and...
Is QoS an issue for VOIP calls over the Internet?
Short answer:
End-to-end QoS is NOT offered on the public ...
- 30k
7
votes
Accepted
Is TCP slow start supposed to be enabled for VoIP SIP?
Should TCP slow start be used with SIP-over-TCP?
SIP does not transfer large data with TCP. SIP is only used for signaling, the transport of the actual data (voice, video, ...) is done with RTP and ...
- 2,408
6
votes
Cisco 3750 - configure to mimic multi location scenario
First, you should probably not use VLAN 1 - it's generally not recommended, or if used, used for network device management traffic only. But, to answer your question, yes, you'd be using inter-vlan ...
- 61
5
votes
VLAN Tags Being Different for a VoIP Phone vs. the Host Daisy-Chained to it?
A VoIP phone that chains to another device is a switch, and it negotiates a trunk between the phone and the switch. This happens with CDP or LLDP.
For example, a Cisco switch interface configured as ...
- 101k
5
votes
VLAN Tags Being Different for a VoIP Phone vs. the Host Daisy-Chained to it?
Certainly this is the usual situation for the Cisco and Avaya phones I'm familiar with, as it's usual to keep voice and data traffic separate.
This is from a Cisco SPA504G phone web configuration; ...
- 16.4k
5
votes
Accepted
Is there a point to have VLANs if each PC client can access them all?
By themselves, VLANs do not offer any security. But you use them to implement layer 3 security.
Remember that VLANs are layer 2 concepts, while IP subnets are layer 3 concepts. In most cases, there ...
- 68k
4
votes
Accepted
VoIP only for two phones
Yes. You can connect 2 IP phones same network (LAN and it should not be exposed to the internet because you'll get ghost calls) and call the other phone by dialing its local IP address, even when the ...
- 156
4
votes
Can I run two separate internet connections over one Cat5e cable
Yes it is possible all you need is a router where both links will get terminated for voice and data it would act as an gateway.
Then you need switch connected via router in switch there would be 2 ...
- 54
4
votes
Accepted
Is an SBC sufficient and can it NAT
From what I understood about SBCs (by virtue of providing the networks, firewalls and routing for SBC deployments), an SBC does not (need to) actually route/forward IP packets between customer and SP ...
- 8,876
4
votes
Accepted
VLAN VoIP and LAN configuration over multiple switches
If all your connections between switches are layer 2, then yes, you need to trunk all VLANs across your backbone switch.
The ports connecting your switches to the backbone will be configured as ...
- 68k
4
votes
Whats the difference between VOICE VLAN and ACCESS VLAN
The access VLAN is what is used for devices, such as PCs, connecting to the switch interface.
VoIP phones can use CDP (or possibly LLDP, depending on the model and switch configuration) to negotiate ...
- 101k
4
votes
Accepted
Whats the difference between VOICE VLAN and ACCESS VLAN
Traditionally with Switching, there are two types of ports:
Access Ports -- ports which carry traffic for only one VLAN
Trunk Ports -- ports which carry traffic for multiple VLANs
In a scenario ...
- 15.2k
3
votes
Accepted
Phone and PC network sharing one wifi bridge
It will work. Keep in mind this to learn why:
1 - A LAN is a single broadcast domain and single collision domain.
Collision Domain: It means that a collision will be sensed by all the devices in the ...
- 4,497
3
votes
Accepted
Mostly wireless campus vs. VoIP
While wireless is a good, convenient, possibly necessary thing for a company to have and use, you don't own the airwaves, and you must be willing to accept any interference that disrupts your Wi-Fi, ...
- 101k
3
votes
VoIP on a remote VPN site
They can be on the same VLAN. That will have no impact whatsoever. Your main potential issue is the lack of QoS on the Internet path. Interestingly, this is a special scenario where disabling split ...
- 4,409
3
votes
Advice on potentially needed subnet expansions
The lack of VLANs probably also means the lack of QoS. In that case you may find you get poor voice quality and your project may not be successful. You really need to upgrade your hardware.
But to ...
- 68k
3
votes
ISP Failover On A Converged Network
Depending on how your network is set up, this is certainly possible.
You can configure the phones to pass VoIP on a dedicated, tagged VLAN and traffic from the internal switch untagged - this is what ...
- 88.1k
3
votes
Accepted
Landline phone on VOIP network without an adapter
No. VoIP over Ethernet is so vastly different from POTS that it's absolutely impossible to connect without a SIP gateway (which might come as an "Ethernet to telephone adapter" but it requires power ...
- 88.1k
3
votes
Accepted
qos inside vpn, possible or not ? I read yes and no
Possible? Generally, yes. However, you need to consider the tunnel outside as well. How effective QoS works depends on a large number of parameters only some of which you have control over.
QoS ...
- 88.1k
3
votes
Accepted
How does UDP provide continuous sound in VOIP even though segments are discrete?
The audio data is "time-compressed" when transmitted.
Imagine a 800 byte UDP datagram carrying 8 kHz 8-bit VoIP data.
The 800 samples cover 1/10th of a second (or 100 ms) when played back. That ...
- 88.1k
2
votes
How do I diagnose a VoIP issue on a Cisco 2811?
for me it sounds like problem in CALL HUNTING configuration
you have two ephone-dn 's (4 & 22) with 2000 extension ,which will handle the incommoding calls, where 4 with preference 0 and 22 with ...
- 3,454
2
votes
Smart switching calls in a company phone calls
Typically in order to handle this type of scenario, you need to add an ACD (Automatic Call Distribution) component to your telephony solution, and tie it into your CRM.
The idea is that your CRM tool ...
- 2,449
2
votes
How is it possible to run VoIP on CAT3. Do you not need CAT5 for the voice data?
Allow me to clarify that It is possible to use cat3 cabling for IP phones in addition to POE.
Since the early 1990s, prior to many IP standards and written documentation for LAN Networks I have ...
2
votes
Do i need to configure VLANS on my router/firewall or just the switch?
From a router perspective, what matters are interface. It doesn't change the router behavior if an interface is physical or virtual.
You can have either two cables between the router and the switch, ...
- 19.8k
2
votes
1-1 NAT on a SonicWall with a DMZ
In this situation, you should put your PBX device in DMZ zone, assign a private IP address for it, then create an Inbound access rule and an Inbound One-to-One NAT policy for public/Internet traffic ...
- 3,754
2
votes
Fortigate 90D SD-WAN: VPN and VoIP
The public IP is nailed to your AT&T router which will be down when it's down. BGP would be required to tell the Internet that your public IP is now accessible via another link.
I don't know of ...
- 4,409
2
votes
Accepted
Advice on potentially needed subnet expansions
I recently went through a very similar VOIP implementation on a 24-bit subnet that was just about full. We decided to shave a bit off the subnet mask as it was a 10.x.x.0 subnet and we didn't have to ...
- 371
2
votes
VoIP, IPsec configuration
Voice Over IP is quite sensitive to latency and jiter (variation in latency).
It is really not surprising that running such a protocol in an emulator on a generic purpose CPU cannot achieve the same ...
- 19.8k
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