Backhaul questions

[avb]

With backhaul upgrades being a major component of Network Vision, I want to ask a few questions.

 

1. Prior to the upgrades Sprint is using T1/bundled T1. T1 can transmit 1.5Mb/s, so how many T1 lines does a typical tower have? If a tower has 10 T1's, that's about 15Mb/s. It doesn't take that many EVDO users to use up that capacity since EVDO rev A can transmit 3.1Mb/s.

 

2. With Network Vision switching to fiber, microwave, or aav for backhaul, how much of an improvement is Sprint expecting to implement? With the bundled T1 example above, an improvement 10 times that amount would be 150Mb/s.

 

3. Will only the new LTE phones see the enhanced backhaul? I'm not clear on eHRPD/EVDO, but it seems like the new LTE phones will use eHRPD when not in a 4g LTE area. Will that be separate from the existing EVDO network? It seems like all of Verizon's 4g outages are always blames on their eHRPD network.

 

4. What type of backhaul is/was Clear using for WiMAX?

 

I'm in Houston, so I'm hoping to see backhaul relieve the 3G issues sooner rather than later.

[S4GRU]

With backhaul upgrades being a major component of Network Vision' date=' I want to ask a few questions.

 

1. Prior to the upgrades Sprint is using T1/bundled T1. T1 can transmit 1.5Mb/s, so how many T1 lines does a typical tower have? If a tower has 10 T1's, that's about 15Mb/s. It doesn't take that many EVDO users to use up that capacity since EVDO rev A can transmit 3.1Mb/s.

 

2. With Network Vision switching to fiber, microwave, or aav for backhaul, how much of an improvement is Sprint expecting to implement? With the bundled T1 example above, an improvement 10 times that amount would be 150Mb/s.

 

3. Will only the new LTE phones see the enhanced backhaul? I'm not clear on eHRPD/EVDO, but it seems like the new LTE phones will use eHRPD when not in a 4g LTE area. Will that be separate from the existing EVDO network? It seems like all of Verizon's 4g outages are always blames on their eHRPD network.

 

4. What type of backhaul is/was Clear using for WiMAX?

 

I'm in Houston, so I'm hoping to see backhaul relieve the 3G issues sooner rather than later.[/quote']

 

1. Sprint uses a lot fewer T1's than most people realize at legacy sites. Some have as few as one in remote sites. The most I can recall ever seeing is like 7 or 8. I don't think I have ever seen 10. The amount of T1's is extremely variable from site to site. I would say on average they use 3 to 4 at most sites.

 

However, in the case of multiple T1's, it doesn't offer faster than 1.5Mbps throughput speeds. It's still limited to the T1's maximum speed of 1.5Mbps. Most sites with T1 backhaul that are not over capacity deliver speeds between 1.0 - 1.4Mbps. So even though between the device and the tower the data may be moving around 3Mbps, it is being slowed down when it hits the T1 backhaul, which is slower. At the sites where 2Mbps+ 3G speeds occur, it's because they have AAV backhaul and not T1's.

 

2. How much? Not sure. There are minimum performance standards outlined with their backhaul vendors that they must meet per contract. However, it will be wildly variable from site to site, but at least meeting the contract minimums. And even the contract minimums should be so much greater than even the site with the most T1's. And most AAV back haul is scalable and more can be added upon request.

 

Since Sprint worked out its backhaul requirements when it thought it was carrying LightSquared traffic too, I have a feeling it is way beyond their needs for a long time.

 

3. Data cannot handoff between LTE and EVDO "naturally", but LTE can handoff to eHRPD. It's my understanding the eHRPD acts as a handoff technology in the middle between LTE and EVDO to provide a more seamless data experience. Verizon and Sprint are both deploying eHRPD. Although eHRPD is problematic and leads to issues, it's my understanding that Verizon LTE outtage issues are caused in their 4G cores. However, perhaps eHRPD is a contributing factor.

 

All devices will see the benefit of new backhaul. Sprint is working on a decommissioning plan for it's T1's to save money. There will be a day when there will be no T1's left anywhere in the Sprint network. Oh, glorious day!

 

4. Clearwire uses mostly microwave backhaul.

 

Robert via NOVO7PALADIN Tablet using Forum Runner

[Sgt. Slaughter]

With backhaul upgrades being a major component of Network Vision, I want to ask a few questions.

 

1. Prior to the upgrades Sprint is using T1/bundled T1. T1 can transmit 1.5Mb/s, so how many T1 lines does a typical tower have? If a tower has 10 T1's, that's about 15Mb/s. It doesn't take that many EVDO users to use up that capacity since EVDO rev A can transmit 3.1Mb/s.

 

2. With Network Vision switching to fiber, microwave, or aav for backhaul, how much of an improvement is Sprint expecting to implement? With the bundled T1 example above, an improvement 10 times that amount would be 150Mb/s.

 

3. Will only the new LTE phones see the enhanced backhaul? I'm not clear on eHRPD/EVDO, but it seems like the new LTE phones will use eHRPD when not in a 4g LTE area. Will that be separate from the existing EVDO network? It seems like all of Verizon's 4g outages are always blames on their eHRPD network.

 

4. What type of backhaul is/was Clear using for WiMAX?

 

I'm in Houston, so I'm hoping to see backhaul relieve the 3G issues sooner rather than later.

 

Welcome to the forums and S4GRU!

 

with that said though, you should first take some time around here to search and read as most if not all of your questions are answered already.

 

Start with the stickies on NV and then even read this thread I started a long time ago on backhaul ?'s I had then.

http://s4gru.com/ind...c/347-backhaul/

 

To answer quickly though:

1) no clue

2) If they are using microwave then the bandwidth is limited but still several GB, and Fiber is basically unlimited in capacity...

3)NO, everyone will experience the backhaul improvements esp those in capacity issue areas where the current backhaul is maxed out

4) no clue

 

Edit:

 

I see el Roberto beat me to the reply here. lol

[S4GRU]

I started on a reply right away, but ate breakfast with my family and answered a phone call. So it took me over 30 minutes to finish the reply.

 

Robert via NOVO7PALADIN Tablet using Forum Runner

[avb]

Thanks for the responses. I've learned so much more about Sprint's network on this site than any other source.

[autoprime]

there was a comment in the LG Viper article page that mentioned in Boston... only those phones using eHRDP would be connected to the new backhaul.

 

so is this something only being enforced now.. since everythings so new? or was the info not correct?

[WiWavelength]

1. Prior to the upgrades Sprint is using T1/bundled T1. T1 can transmit 1.5Mb/s, so how many T1 lines does a typical tower have? If a tower has 10 T1's, that's about 15Mb/s. It doesn't take that many EVDO users to use up that capacity since EVDO rev A can transmit 3.1Mb/s.

 

EV-DO Rev A downlink has throughput up to 3.1 Mbps per carrier per sector -- not per user. So, it would not matter how many EV-DO users are connected, their aggregate downlink data transfer could not exceed 3.1 Mbps per carrier per sector.

 

AJ

[Sgt. Slaughter]

I started on a reply right away, but ate breakfast with my family and answered a phone call. So it took me over 30 minutes to finish the reply.

 

Robert via NOVO7PALADIN Tablet using Forum Runner

 

yeah i had to search for my older thread so i wasn't the quickest response either. lol

[Sgt. Slaughter]

Thanks for the responses. I've learned so much more about Sprint's network on this site than any other source.

 

yeah that is the norm around here. lol

 

youll get used to that feeling after awhile and just ignore the rest in regards to network talk.

[S4GRU]

there was a comment in the LG Viper article page that mentioned in Boston... only those phones using eHRDP would be connected to the new backhaul.

 

so is this something only being enforced now.. since everythings so new? or was the info not correct?

 

There are some isolated issues with EVDO backhaul connection. If the enhanced backhaul is in place at the site and ready to go when the site is converted to NV, the EVDO gets connected to the new backhaul. If the new backhaul is not ready at that time, then they temporarily connect it to legacy backhaul. They will then connect it to the new backhaul on the next truck roll. Most likely when LTE is brought live at the site.

 

Robert via NOVO7PALADIN Tablet using Forum Runner

[autoprime]

There are some isolated issues with EVDO backhaul connection. If the enhanced backhaul is in place at the site and ready to go when the site is converted to NV, the EVDO gets connected to the new backhaul. If the new backhaul is not ready at that time, then they temporarily connect it to legacy backhaul. They will then connect it to the new backhaul on the next truck roll. Most likely when LTE is brought live at the site.

 

Robert via NOVO7PALADIN Tablet using Forum Runner

 

ahhh.. it's all clear now. thank you for the break down.

[Sgt. Slaughter]

Was thinking about this today and realized it really is a good question to ask how much backhaul they are going to be using...just b/c microwave radome can handle a couple GB bandwidth, that by no means Sprint will be using all of it...Wonder how the contracts they have for them are, as in if price of enabling more bandwidth form the radome would cost them more and they would choose to sit on it for awhile instead of putting $ down...Also wonder how fast they could scale up the bandwidth and if it would even req a truck roll at all by anyone involved. I'd assume not and it'd be no different than you calling TWC and upgrading your broadband plan to the next tier and getting more speed...They could call whoever and say they need more and get it instantly...

 

OR is all this nonsense and the radomes are all connected to their own network so they are not paying another provider like they would for T1's to be run?

[S4GRU]

In reality, microwave backhaul is most often limited where it connects to the internet, not in the microwave links themselves.

 

In most instances, where microwave is connected to the internet, it is a fiber connection. However, it may possibly be an AAV connection. Also, not all fiber connections are equal.

 

I am not able to completly answer your question, as there are too many variables to come up with a comprehensive response. I just know that even with microwave backhaul vendors, they have minimum performance standards. I believe that scalability is included in all the contract requirements based on the things I have read. Sprint is smart not to get itself in a corner with future backhaul needs at these sites its adding backhaul at now.

 

When and if they need more, it should be a simple request from the backhaul vendor for more. The contract probably spells out 45 day or 90 day response time to the request. And now with the much improved network monitoring, Sprint should be able to keep way ahead of the backhaul curve. But I also believe the initial backhaul is enough to service several loaded LTE carriers. As Sprint was planning LTE 1900, LTE 800 and two LS LTE carriers when it was planning Network Vision.

 

Robert via NOVO7PALADIN Tablet using Forum Runner