dslreports logo
site
 
    All Forums Hot Topics Gallery
spc

spacer




how-to block ads


Search Topic:
uniqs
3759
share rss forum feed

cooldude9919

join:2000-05-29
kudos:5

DS3 Point To Point

We are checking into several redundacy options for 2 offices of ours. One option is to get a DS3 point to point. I am trying to get all equipment costs together for this, and i have some questions.

Endpoint devices will either be cisco 3845's or 2821's

From what i can tell, we should be able to use the older NM-1A-T3 card is that correct? It can be had for ~$100 or less off ebay, whereas the newer NM-1A-T3/E3 cards are $4000.

Now could we channalize the ds3 if we wanted? Aka we have a point to point t1 we want to cancel to the same office, and then pass it over the new ptp ds3. From what i can tell there are no channalized cards for the newer ISR routers? Only the older 72xx routers is that correct? If so then i guess i could just buy one of those routers and cards for each end?

Thanks!

aryoba
Premium,MVM
join:2002-08-22
kudos:4

2 edits
What you can consider is to bring in managed circuit service. The point-to-point provider will fully manage the circuit and you only deal with Ethernet handoff from them. With Ethernet handoff, you don't need to worry about CSU/DSU and just deal with the Ethernet itself.

Channelized DS-3 should not be a concern on your end unless you plan to manage the channelization yourself. The circuit provider can pretty much lock your bandwidth from partial to full DS-3. At any time, the provider can adjust the bandwidth to fit your need and budget.

As a food of thought, you may want to tell the circuit provider if they support Layer-3 MPLS VPN over the circuit, in case you need to have some VRF in your network. VRF is the way to go in case of sharing the same equipment and circuit to carry multiple networks that can never see each other (read: to have multiple networks that each has its own routing table).

cooldude9919

join:2000-05-29
kudos:5
said by aryoba:

What you can consider is to bring in managed circuit service. The point-to-point provider will fully manage the circuit and you only deal with Ethernet handoff from them. With Ethernet handoff, you don't need to worry about CSU/DSU and just deal with the Ethernet itself.

Channelized DS-3 should not be a concern on your end unless you plan to manage the channelization yourself. The circuit provider can pretty much lock your bandwidth from partial to full DS-3. At any time, the provider can adjust the bandwidth to fit your need and budget.

As a food of thought, you may want to tell the circuit provider if they support Layer-3 MPLS VPN over the circuit, in case you need to have some VRF in your network. VRF is the way to go in case of sharing the same equipment and circuit to carry multiple networks that can never see each other (read: to have multiple networks that each has its own routing table).
ATT is the only option for the PTP due to the sites locations, and as such the price quotes are high enough already. A managed solution would only make things worse, so we would be looking at a non managed solution.

If i can infact use the cheaper cards, then i already have the routers i need, if we want to go down the non-channalized road that is. We would only be looking at ~$200 in equipment costs to get it up and going.

aryoba
Premium,MVM
join:2002-08-22
kudos:4

1 edit
said by cooldude9919:

ATT is the only option for the PTP due to the sites locations, and as such the price quotes are high enough already. A managed solution would only make things worse, so we would be looking at a non managed solution.
Is there a reason why it has to be point-to-point? How about MPLS which usually cost less then point-to-point?

cooldude9919

join:2000-05-29
kudos:5
said by aryoba:

said by cooldude9919:

ATT is the only option for the PTP due to the sites locations, and as such the price quotes are high enough already. A managed solution would only make things worse, so we would be looking at a non managed solution.
Is there a reason why it has to be point-to-point? How about MPLS which usually cost less then point-to-point?
I wouldnt be against that, but i am not sure if that is true in our case but i will be double checking that.

nosx

join:2004-12-27
00000
kudos:5
Most businesses take a dual-cloud approach for redundancy.
Either two different mpls clouds (think one network from verizon, one from sprint)
or an mpls network and an ipsec internet tunnel for backup.
Both are common approaches and dont involve private line circuits or expensive hardware.

A word of caution regarding ethernet access circuits: Intermediate failure will not cause your neighbor to go down. The DS3 or OC3 or larger between add/drop multiplexers used by the telco to deliver your ethernet access circuit will never go down, so your routing will be slow to converge, resulting in larger outages in the event of a failure.

cooldude9919

join:2000-05-29
kudos:5
I appreciate everyones suggestions, but in our case this seems to be the best options. MPLS is out due to the amount of bandwidth we need plus the smaller city size of my location, meaning not many options.

The only other real possible option would be getting another internet circuit at each site and using bgp to load balance, which i am getting quotes on.

FYI cheapeast quote i have gotten on the ptp ds3 is $3k.

In my location the cheapeast and only other internet circuit option is a ds3 that at the lowest possible commit (4mb or something like that with the ability to burst to full 45mb) would run us around ~2k.

That leaves ~1k for the other office which would be a tight fit for the bursting ability we need.

I would still appreciate an answer to the question in my first post.

nosx

join:2004-12-27
00000
kudos:5
Regarding the first post, any of those ...-1A-... cards are for ATM. They are not channelized, and they are not clear-channel. They are ATM circuits. That is why they are so cheap. If you dont want ATM, and dont have ATM hardware you shouldnt be looking at them. Also, the 28XX is incapable of routing a DS3. The 3845 is the lowest end router that is reccomended for that role. You would be better off price-wise getting a 7200.
Also, if you want to use the DS3 as an access circuit and channelize it, the card is different than (and significantly more expensive) than a clear-channel version.
You should be aware what the topology is between your sites through the telco to make sure the equipment you are ordering, and the circuit you are purchasing are all compatible.

aryoba
Premium,MVM
join:2002-08-22
kudos:4
reply to cooldude9919
said by cooldude9919:

Now could we channalize the ds3 if we wanted?
Is there a reason why you need a channelized DS-3? Are you trying to terminate both voice and data on the same circuit?

aryoba
Premium,MVM
join:2002-08-22
kudos:4

1 edit
reply to cooldude9919
said by cooldude9919:

If i can infact use the cheaper cards, then i already have the routers i need, if we want to go down the non-channalized road that is. We would only be looking at ~$200 in equipment costs to get it up and going.
Another consideration is to have AT&T (or other possible telco/ISP) to manage just the DSU/CSU. On your router, there might be a HSSI module to terminate the DSU/CSU. As nosx See Profile mentioned, you need to be aware of the circuit topology to ensure you have the proper equipments.

cooldude9919

join:2000-05-29
kudos:5
reply to aryoba
said by aryoba:

said by cooldude9919:

Now could we channalize the ds3 if we wanted?
Is there a reason why you need a channelized DS-3? Are you trying to terminate both voice and data on the same circuit?
Possibily yes

cooldude9919

join:2000-05-29
kudos:5
OK,

So i need to figure out if the circuit will be ATM or not.

If it is i can use the NM-1a-t3

if its not i would be using the NM-1T3/E3

right?

If i want to channelize it what would i check into using?

aryoba
Premium,MVM
join:2002-08-22
kudos:4
said by cooldude9919:

if its not i would be using the NM-1T3/E3
right?
There is NM-1HSSI module you can consider that needs an external CSU/DSU. You should be able to have the telco/ISP manage this external CSU/DSU while you manage the NM-1HSSI module. Note that this module is EOL.

said by cooldude9919:

If i want to channelize it what would i check into using?
I believe you need at least 7200 series to support channelized DS3, which mean different module type.


TomS_
Git-r-done
Premium,MVM
join:2002-07-19
London, UK
kudos:5
reply to cooldude9919
You could look at using AToM to transport your T1 via MPLS from one site, over the DS3, and then pop it out at the other end.

That way you dont need channelised line cards, you will just operate a routed network as per normal, with a bit of MPLS thrown in the mix.

cooldude9919

join:2000-05-29
kudos:5
Overture Networks ISG45+ looks interesting if i want a stand alone unit.

»www.overturenetworks.com/product···-45.html

Any thoughts on that?
Where the hell do you buy overture networks stuff from? I cant seem to find any online stores.

nosx

join:2004-12-27
00000
kudos:5
Anda and Overture are companies geared toward the telco and carrier market, they dont have much interest in supporting small end users that only want a pair of units. Unless you are Verizon and buy 5000 overture boxes, i wouldnt count on getting very far with them.

cooldude9919

join:2000-05-29
kudos:5
anyone use devices from RAD? Been talking to them and they seem to know thier stuff. I could do what i need with their RICI-16 device, that can now come with t3 ports.