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Showing content with the highest reputation on 04/05/2019 in all areas

  1. 15 points
    Josh HillSprint 4G Rollout UpdatesFriday, April 5, 2019 - 3:06 AM PDT Now that VoLTE is actually rolling out on Sprint, it's a good time to dive into what exactly is VoLTE, and how is it different from Calling+ and VoWiFi (Wifi Calling). Background Terms E-UTRA or EUTRA: Stands for Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access. This is the technical name for the actual LTE airlink. QoS: Quality of Service. This is a way of tagging / flagging certain types of traffic to have priority above or below other traffic. When traffic has a QoS tag higher than other traffic, network equipment (the tower, routers, etc) will drop or ignore lower priority traffic to ensure that this traffic goes through instead. The equipment can also be configured to reserve a certain amount of bandwidth to only be used by traffic with a particular QoS tag. For example, if a router has 10 Mbps available, it can allocate 1 Mbps for a certain QoS tag. Normal traffic will only be able to use 9 Mbps, with 1 Mbps reserved for that QoS tag. The number of QoS priorities / tags varies between equipment vendors, but can be in excess of 256 priority levels. QCI: QoS Class Identifier. This is a value that an LTE / E-UTRA session can be assigned that corresponds to a particular QoS tag and specific attributes of that particular QoS queue. For example, it may or may not specify a guaranteed/dedicated bandwidth allocation (GBR). APN: The APN is the name of the gateway on a mobile network. It identifies the packet data network that should be used for that E-UTRA session. IMS: IP Multimedia Subsystem. It is a method for sending SMS over LTE, along with setting up VoLTE calls and other signaling. eCSFB: Circuit Switched Fall Back. For phones / UEs that can only listen on either LTE or CDMA rather than both simultaneously, it is a method for the LTE network to tell the device that a call is coming in, and to switch over to CDMA to process it. SRLTE: Single Radio LTE. This is a capability of newer devices that allows them to listen on both CDMA and LTE at the same time, but only transmit on one at a time. This replaces the need for eCSFB, allowing the device to see a call coming in over CDMA while it’s using LTE. It is also more reliable and reduces the number of missed calls due to failed fallback. When a call is active, the LTE session is stopped / paused. SIP: Session Initialization Protocol. This is the standard protocol for VoIP in telecom networks. How VoLTE Works While we typically think of LTE as a single connection, multiple E-UTRA “sessions” can actually be established, creating what are essentially virtual/multiple LTE interfaces, each with their own IP address, QoS level, APN, etc. Each session has a numerical QCI assigned that dictates the actual QoS priority and whether or not it has a GBR (Guaranteed Bitrate). QCI Resource Type QoS Priority Packet Delay Budget Packet Error Loss Rate Example Services 1 GBR 2 100ms 10−2 Conversational Voice 2 GBR 4 150ms 10−3 Conversational Video (Live Streaming) 3 GBR 3 50ms 10−3 Real Time Gaming, V2X messages 4 GBR 5 300ms 10−6 Non-Conversational Video (Buffered Streaming) 65 GBR 0.7 75ms 10−2 Mission Critical user plane Push To Talk voice (e.g., MCPTT) 66 GBR 2 100ms 10−2 Non-Mission-Critical user plane Push To Talk voice 75 GBR 2.5 50ms 10−2 V2X messages 5 non-GBR 1 100ms 10−6 IMS Signalling 6 non-GBR 6 300ms 10−6 Video (Buffered Streaming) TCP-Based (for example, www, email, chat, ftp, p2p and the like) 7 non-GBR 7 100ms 10−3 Voice, Video (Live Streaming), Interactive Gaming 8 non-GBR 8 300ms 10−6 Video (Buffered Streaming) TCP-Based (for example, www, email, chat, ftp, p2p and the like) 9 non-GBR 9 300ms 10−6 Video (Buffered Streaming) TCP-Based (for example, www, email, chat, ftp, p2p and the like). Typically used as default bearer 69 non-GBR 0.5 60ms 10−6 Mission Critical delay sensitive signalling (e.g., MC-PTT signalling) 70 non-GBR 5.5 200ms 10−6 Mission Critical Data (e.g. example services are the same as QCI 6/8/9) 79 non-GBR 6.5 50ms 10−2 V2X messages (source: https://en.wikipedia.org/wiki/QoS_Class_Identifier) As you can see in the above table, the QCI does not necessarily correspond to the QoS level. For example, QCI 1 has a QoS priority of 2, but QCI 5 has a QoS priority of 1, making it actually higher priority traffic. On Sprint, traditionally one E-UTRA session was used, with a QCI of 9 and QoS priority of 9. This is the lowest QoS priority, and does not have a guaranteed bitrate. On devices which use eCSFB or VoLTE, another E-UTRA session is established for the IMS APN using a QCI of 5 and QoS priority of 1, and is used for IMS. This session also does not have a guaranteed bitrate, but it has the highest QoS priority. IMS is used for SMS over LTE, along with setting up VoLTE calls. eCSFB devices use it for SMS, and likely also for triggering eCSFB. On newer device which instead use SRLTE, IMS is not used unless VoLTE is enabled, and they instead use CDMA 1x for SMS, so an IMS E-UTRA session is often not setup. When a VoLTE call is initiated, a third E-UTRA session is established, also using the IMS APN. This session has a QCI of 1 and QoS priority of 2. Unlike the other two sessions, this one does have a guaranteed bitrate. For Sprint, this bitrate is 39 Kbps. The screenshot below shows all 3 sessions: VoLTE E-UTRA sessions This is how VoLTE calls are prioritized over regular data. Normal data usage, such as loading a web page or watching a video, will still use the lower, default QoS (QCI of 9), while the data for the VoLTE call will be at the second highest priority (QCI 1), just after IMS signaling (QCI 5). The tower / eNB will ensure that the VoIP session always is able to use up to 39 Kbps by reserving that bandwidth and dedicating it to the call. This is in contrast to “Calling+”, which does not establish a separate E-UTRA session, and instead uses the normal QCI 9 session. The below screenshot shows an active Calling+ call. Note the presence of only a single E-UTRA session. Calling+ E-UTRA sessions So now that we have the airlink for VoLTE, what happens? VoLTE, Calling+, and VoWiFi are essentially standard SIP VoIP calls. The below screenshots show the SIP details for an active call, and the LTE Signaling messages that setup and then end the SIP call. VoLTE SIP details VoLTE Signaling For VoLTE, the traffic for the SIP call goes over the QCI 1 E-UTRA session instead of the normal QCI 9 session. This means that the eNB (tower) will reserve and guarantee 39 kbps for the call, but other traffic from the same device will not be prioritized and will use the normal session. So starting a VoLTE call will not make the rest of your traffic prioritized, it will apply only to the VoLTE call. So as a recap, when VoLTE is enabled, the UE / phone establishes multiple E-UTRA sessions. One is used for normal usage, one is used for texting and signaling, and one is used for the VoLTE call. Think of these like separate virtual ethernet cables. On the QoS prioritized and guaranteed bitrate VoLTE session, the UE establishes a SIP VoIP connection for a call. On Calling+ devices, the same SIP connection is used, however it runs over the default QCI 9 session instead, and therefore isn’t prioritized and doesn't have a guaranteed bandwidth. This is why Calling+ calls are more likely to cut out or not sound as good. VoLTE call Calling+ call VoWiFi (Wifi calling) operates almost the same way. Like VoLTE and Calling+, it also uses the same SIP connection for calls and presumably IMS for signaling, but instead of using an LTE E-UTRA session, the phone establishes an IKEv2 IPsec VPN connection to Sprint. This is an encrypted connection that allows data to be tunneled directly into Sprint’s network. The SIP and IMS traffic are then routed over this VPN to Sprint, but not other, normal traffic. From a QoS perspective, VoWiFi is identical to Calling+, in that neither are prioritized above other traffic. VoWiFi call Because VoLTE, Calling+, and VoWiFi all use the same SIP servers and connections, under normal conditions they sound the same and can technically hand off to one another. They can all take advantage of HD Voice codecs and should sound the same, since the call itself is identical across all three. The difference is how the data for that call makes it to Sprint. VoLTE is able to use a dedicated, guaranteed airlink to ensure that congestion on the network (LTE or WiFi) won’t adversely affect the call. One final performance benefit is that VoLTE is able to take advantage of something called RoHC (Robust Header Compression), seen in the above 3 screenshots. This compresses the IP, TCP, UDP, and RTP headers from 60 bytes to 1-3 bytes, resulting in up to 60% bandwidth savings. It’s only possible on a dedicated link, which is why VoLTE has it but Calling+ and VoWiFi do not. So not only does VoLTE have guaranteed, dedicated bandwidth, it will use potentially half as much, which matters a lot for maintaining the call in edge of cell scenarios.
  2. 5 points
    VoLTE post is up! https://s4gru.com/entry/439-sprints-casting-call-of-voice-over-actors-an-in-depth-analysis-of-volte-calling-and-vowifi/ Sent from my Pixel 3 XL using Tapatalk
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    New beta is finally done brewing and has been uploaded to Google Play.. should be available within the hour! Lots of significant bugfixes and new LTE alerts that should make people very happy. Changelog: https://signalcheck.app/change-log Thanks for your patience, and let me know what I broke.. -Mike
  6. 2 points
    Just a quick update for the Beta Crew, yes I am still hacking away at the new Alerts.. it is a lot of work trying to get everything working well on Oreo+ devices while not breaking pre-Oreo devices. I forgot how many ugly workarounds I needed to implement to keep everything working before. The new Android notification settings don't mesh well with my needs either, but it will get done. Just a tedious struggle. Side note, I accidentally stumbled across something I either didn't know or forgot about.. Pie introduced a new method to get the channel bandwidth, so hopefully that will be an easy and very cool addition making this wait worth it.. stay tuned.. -Mike
  7. 1 point
    Storage Room Sent from my SM-N920P using Tapatalk
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    Here you go fren. https://techship.com/products/sierra-wireless-em7511/
  10. 1 point
    FierceWireless got comments from both OpenSignal and Ookla about the results. https://www.fiercewireless.com/wireless/at-t-claims-fastest-network-ookla-results-raising-eyebrows
  11. 1 point
    Yeah I have seen a few now that we are getting the big rollout treatment here. They are popular with the newer, thiccer builds. Last round was MiniMacro that have four port antenna, with 2 utilized. Our site is the only one in any form of city limit without it, that gotdang monopole crushes me. We have a town named Aynor here, it has about 400 people, and an 8t8r with 4 carriers live so there is that. I believe user @Terrell352 can appreciate that the cows in SC being covered as well as the cows in FL, finally. Anyhoo, With all the funky spacing in US band 41, is there room for 3 carriers on that model? Maybe 15 L and 40 NR or just ~50 NR? Do you know if ROK operates in the full band? Maybe they got a great deal on them. Sprint does tend to be thrifty with the gear spend lately, and that shows in how far they are making progress go so quickly. I imagine a split sector running that bad dude in areas they are 2.5 constrained to the high end. Aynor will probably get the 120MHz model though, since we have spectrum like that to spend here
  12. 1 point
    It was a Korean OEM model who Samsung partners with. You've probably see plenty of their sector antennas and 800 MHz Rrus (ALU rebranded) around. For the AAHE it's B41 TDD. B7 is paired 2500-2570/2620-2690. It's just interesting to note as usually sprint gear is set to B41H (2618-2690) or B41L (2506-2570) and then you have an AAHE that's just out there above the typical BRs high range. Sent from my Pixel 3 using Tapatalk
  13. 1 point
    I had my F35 lightning account carrying large metric tonnage of ordinance and set to maximum shit poasts per sq kilometer. Mission aborted. Even when Mr. Tim presents humble he shares with us his amazing input and excellent knowledge base and gives us more cool facts. Were the other units Chinese or foreign? They also seem to have a lot of 2.6, and is the AAHE a possible band 7 solution for other operators or TDD only? Just curious about gear as usual. Looks like AAHE could be a sweet NR solution next to some LTE cells on differing but co-located hardware.
  14. 1 point
    Thank you for making me double check the vendors equipment and past statements about it and 120 MHz is stated for at least the Nokia AAHC M-MIMO. I eat humble pie today good sire. Looks like I saw the specs for a 2.5 GHz M-MIMO from another related (non-Sprint) vendor which did have a 100 MHz IBW and applied it to the rest for some reason. Please correct that if you see it posted elsewhere by informing others or reminding me to cross out the inaccurate information. I do see NR C2PC's for the Nokia and Samsung units and a brand new Ericsson M-MIMO filing using another FCC ID. Fun Fact: Did you know Sprint / Nokia uses 2 M-MIMO Models? AAHC = Full Band 2596-2690 while AAHE is 2630-2690.
  15. 1 point
    Man you have to give Saw credit, he has worked with so much first generation equipment, and had to use it to make due while his bosses have inflicted so many half tested solutions on their UE's. Though I do wish he would clarify this. It's not just a forum user stat, he is out there on tape and now putting it in front of the merger as this specific equipment operating as you highlighted. Like Mr. Tim said though, the gear is the gear. So maybe he is just accounting for some spectrum usage compromisetry that he has afoot between the two airlinks. Since it is now a part of the merger argument, again he does need to address it. I suggest the executive twitter account carpet bomb solution; squeaky wheels, grease and such.
  16. 1 point
    I found a new AT&T iDAS installation last week at the Belterra Casino in Indiana. It has been installed since my last stay there back in October. It was only broadcasting B12/B66, no MFBI for B17 or B4. My dad's older phone wouldn't see it or connect to it at all, and when I locked my phone to only B4 I couldn't see it or connect to it. There was also no CA between the two bands. The iDAS covered the 15 floor hotel as well as the entry, restaurant, and shopping area up to where you actually get on the casino boat. They did not install it on the boat itself, I could barely get an HSPA+ connection while on the boat. The setup used the same GCI and PCI sector throughout the entire facility. The nodes are very inconspicuous and almost look like round ceiling speakers. They were installed about every 30-40 feet in the hotel area. Speed was impressive, and much better than the < .5mbps I got on the hotel wifi. The B12 carrier was 5x5, the B66 carrier was 20x20.
  17. 1 point
    Can you explain why John Saw says differently? He is definitely saying Massive Mimo supports 120mhz. “What’s most amazing though about this breakthrough technology is the impact it’s having on the network experience for our customers already. We’re rolling out Massive MIMO equipment in Los Angeles and other cities using 60 MHz of 2.5 GHz spectrum to dramatically increase capacity on our existing 4G LTE Advanced sites. This technology is particularly suited to high-traffic urban locations and the early performance results are exciting. For example, during the past three weeks at the LA County Fair, we’ve seen a huge up to 5X increase in our LTE capacity and speed using our newly deployed Massive MIMO radios compared to 8T8R. That’s giving Sprint customers at one of the largest county fairs in the U.S. a better network experience because we’re moving more data, more quickly, to more people.” “And the story gets even better! In the first half of next year, our team will make a simple software upgrade to our base stations (no tower climbs needed), and we’ll also light up 5G service on these same Massive MIMO radios using an additional 60 MHz of 2.5 GHz” Sent from my iPhone using Tapatalk
  18. 1 point
    Excited to see this. Columbus market seems to be doing pretty well for me lately. Already getting 120-150mbit at home/work and even see speeds around 250mbit along 33 southeast of Canal.
  19. 1 point
    The FCC clock begins to count again tomorrow. Do you think we will get any action this week? The longer they take to review the more the opposition has to cause issues. After nearly a year... I'm thinking the DOJ or FCC would have called it off by now, but who knows?
  20. 1 point
    Hence the roaming agreements with ATT and T-Mobile. Forced to use VoLTE for calls and pay the roaming fees for it. Helps that Sprint has aggressively been upgrading clear towers to Triband too!
  21. 1 point
    I thought the roaming agreements with AT&T and T-Mobile were data only?
  22. 1 point
    Which is the reason for roaming agreements with AT&T and T-Mobile
  23. 1 point
    I'm curious as to what will happen with the Verizon roaming agreement since they are shutting down their CDMA network at the end of the year. They provide a lot of voice roaming coverage for Sprint.
  24. 1 point
    US Cellular maybe? Totally dismantle towers and expand the roaming agreement? Or discontinue expansion in these areas and expand the roaming agreement? Become SoftBank US and do a total rebrand?
  25. 1 point
    1) advertise their 5G service coverage areas 2) find another merger partner 3) abandon service in unprofitable parts of the country by striking a longer term roaming deal with T-Mobile 4) change their name to match their related Japanese carrier and/or merger with them
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