Re: [Bloat] Does 5g have the bloat problems of WiFi?

Re: [Bloat] Does 5g have the bloat problems of WiFi?

[Dave Taht]

This is one of those philosophical questions that covers a lot of
ground under the 5g moniker.

0) This looks like a paid placement structured like an infomercial.
AT&T would dearly like X$/month from every device
connected to the network, selling microcells and carrying all your
traffic back to the cloud. The robot company is cute. The
story claiming this offloads the instore wifi - not so hot. Usually
the opposite claim is made.

1) For starters, it IS looking like AT&T etc, completely missed the
bufferbloat problem:

https://www.reddit.com/r/verizon/comments/9lqp6n/i_got_5g_home_internet_installed_this_week_and_it/

(I've got more links than this and have had a rather discouraging talk
with one of AT&T's managers )

Ericcson and a few other LTE related folk haven't, but they don't seem
to have products yet.

Perhaps they'll learn.

1a) For handsets there are decent cross layer techniques also.

2) But I think the thrust of the article re bandwidth and conflating
bufferbloat into it are *both* wrong. It's more a matter of how many
devices you can pack onto a given AP/microcell in a given area, which
is both a function of how good your (MU)-mimo is...
and how fast the mac can switch between them. Inter-device latency, not bloat.

And that's kind of anybody's guess at the moment. Including what 5g is
- 802.11d? y? a zillion other standards come under this umbrella. what
frequencies are you going to use? etc.

("bufferbloat" isn't a problem unless these robots are using huge
amounts of bandwidth, and I'd hope the were mostly just uploading
positional and other sensor data, rather than, say, a 360 degree
camera feed. However using the spectrum effeciently as the fq_codel
for wifi work did, certainly helps that)

(And were it me, I'd WIRE up the cash terminals, and sure as heck not
share the corp wifi with customers)

This being one of my bad days, I think the 5g/4g takeover is
inevitable given the billions being poured into it relatve to the
paltry investment into wifi. Outsourcing all the details as to how
your robot runs around, verses actually running a wire to your shop
and getting multiple APs right, few dead spots, is too hard to
maintain, handoffs too painful.

On my good days I point to intel doing a great job on their wifi chips
and closing down their LTE division, as an example that
LTE is actually far more difficult to make and make work than wifi is.
As well as nobody wants to have a sim card for ecery device they own
or outsource all their traffic to the cloud. WifI is still loved. It
is still a lot better than LTE in most coffee shops.

PS But vs the cost of the robot vs the cost of the wireless chipset,
I'd see 'em all equipped both ways and be letting the
customer decide.


On Thu, Aug 1, 2019 at 3:38 PM Kenneth Porter <shiva@sewingwitch.com> wrote:
>
> I just saw this article claiming that 5g is allowing brick-and-mortar
> automation providers to overcome limitations in WiFi, and I'm wondering if
> the technology is going to suffer from all the same problems previously
> seen in WiFi.
>
> <https://www.zdnet.com/article/googly-eyed-robots-actually-important-5g-edge-computing-benchmark/>
>
> (The "googly-eyed robots" in the title are man-sized robots that wander
> grocery stores to visually track inventory. Someone put googly eyes on them
> to keep them from scaring customers.)
>
> _______________________________________________
> Bloat mailing list
> Bloat@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/bloat



--

Dave Täht
CTO, TekLibre, LLC
http://www.teklibre.com
Tel: 1-831-205-9740

Re: [Bloat] Does 5g have the bloat problems of WiFi?

[Dave Taht]

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Informative post, thank you!

On Thu, Aug 1, 2019 at 5:43 PM Kirn Gill <segin2005@gmail.com> wrote:
>
> Replying to Dave Taht,
>
> There's a few considerations here:
>
>  - What is "5G"?
>
> Strictly speaking, 5G is ITU-T's IMT-2020 standard(s). So far, there
> is only one system under this standard, 3GPP's New Radio (NR). NR is
> what is meant as 5G in layspeak.

I think I will try to talk directly to "NR" in the future rather than
the overloaded term 5G.

> The NR air interface is defined in 3GPP TS 38.xxx series documents.
>
> Against point 2, about operators simply wanting more active SIMs to
> charge for, it's worth noting that NR can be deployed for private
> operation; the company that's using the service could itself own the
> entire network it's using. There are companies using private LTE
> networks for V2x and remote sensing, see for example:
> https://steelguru.com/mining/l/532247, or contract a third party to
> build a dedicated network:
> https://www.zdnet.com/article/telstra-deploys-private-lte-network-in-png-volcanic-crater-gold-mine/

I agree that for a large company in these circumstances it makes sense
to think about deploying LTE
on their own. It's not just the latency

In terms of

>
> NR operates over commercial and unlicensed frequency bands. The
> specific frequency bands defined for the system are listed in 3GPP TS
> 38.104 (Rel. 15) section 5.2
>
> 802.11a/b/g/n/ac/ad use CSMA/CA - Carrier Sense Multiple Access with
> Collison Avoidance - as their multiple access scheme, same as 802.3.
> Each transmitter completely owns the medium when transmitting.
>
> 802.11ax, LTE, and NR use OFDMA - Orthogonal Frequency Division
> Multiple Access - as their multiple access scheme. Instead of the
> transmitter having the full channel for the duration it is
> transmitting, OFDMA takes OFDM modulation and divides not only across
> timeslots/timed transmission frames, but also by subdividing the full
> channel into simpler "resource blocks" with a fixed number of OFDM
> tones.

There are a ton of folk here that would really like to get their hands
dirty on both these techs but our hands are tied by the lack of open
source drivers and firmware.

>
> LTE and NR have many features that Wi-Fi lacks which results in a far
> superior user experience. OFDMA, only recently adopted for 802.11ax

As for the "far superior user experience"... multiplexing any amount
of data over
present day LTE on every network I've ever tried has been a miserable
experience.

The context of the article was robots, moving it back to
bufferbloat... attached are two test runs of flent (up and down) on my
t-mobile tether taken just now. 1000ms of induced latency (baseline of
40) one way, 256ms the other. That's worse than comcast... a far cry
from the 20ms I get under load on wifi today.

My usb-lte stick doesn't even come close to this good,

All the lte-network gateways I've tried to date are a separate double
natting full ip stack box in the 300+ dollar range. The last one I
tried
crashed every other day. It had pretty lights though.

I've yet to have a tethered box actually do dhcp-v6pd, and being
behind cgnat is not a superior internet experience. Having a dedicated
static IPv4/v6 would be nice.

Admittedly to fix both the ipv6 and cgnat issues I just run a
wireguard tunnel. But we'd need to debate what is meant by user
experience. And/or someone identify a NR box a geek could love?

> ("Wi-Fi 6"), generally results in far superior throughput rates than
> CSMA/CA when many users are involved.

Still waiting to test decent examples of both standards. This year is
looking promising.

> In LTE and NR, this is also
> optimized further with centralized (at the eNB/gNB) MAC scheduling for
> all traffic on both uplink and downlink.
>
> Inter-cell handover in all cellular systems is much better than in
> Wi-Fi; Wi-Fi is a mobile-only system where the mobile station is in
> full control of the process, and it's a "break before make", that is,
> the mobile station fully disassociates from the first access point
> before associating with the next access point, even in the case of a
> shared BSSID and background Ethernet network. It's like unplugging
> from one Ethernet port and plugging into another one rather quickly,
> complete with the brief hiccup in network applications.

For about 10 years now, I've run the babel adhoc routing protocol,
there's no break before make there either. But I concede most of this
point on normal wifi AP's with crypto on.

However, celluar backhaul's stuff often quite a long ways - 40ms
in my example case, wifi "mobile" IP (moving within a warehouse) on wifi
being pretty fast (4ms) relative to the local network.

> Cellular is a lot better; the mobile station scans for neighboring
> cells to the one it's connected to in it's spare time, and sends this
> list to the network, so that the base station can "see" the different
> signal strength's from the mobile station's perspective. The network
> then instructs the mobile station to make a blind jump to whichever
> cell it feels will best serve the mobile station and reduce power
> consumption on that end. "Association" is with the network itself, not
> with individual base stations, so there's no need to do the "break
> before make" dance of Wi-Fi.

While I strongly agree that the NR mac is better even than wifi6, the
cell makers
have gotta tackle the bufferbloat and IPv6 issues. I have some hope some
have paid attention.

>
> --
> Kirn Gill II
> Mobile (SMS only): +1 813-300-2330
> VoIP: +1 813-704-0420
> Email: segin2005@gmail.com
> LinkedIn: http://www.linkedin.com/pub/kirn-gill/32/49a/9a6
> _______________________________________________
> Bloat mailing list
> Bloat@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/bloat



-- 

Dave Täht
CTO, TekLibre, LLC
http://www.teklibre.com
Tel: 1-831-205-9740

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Re: [Bloat] Does 5g have the bloat problems of WiFi?

[Kirn Gill]

Oh, as an addendum, that whole dance that cellular does with
inter-cell handover is known as "mobility management". There's also
mobility management commands sent between base stations, or base
stations and a control hub, which make the handover seamless and
remove the requirement that the mobile station reauthenticate on each
jump, like it must do with Wi-Fi - the mobile station will be provided
all the parameters needed to instantly begin communication with the
new cell via it's connection to the old cell before the jump is
executed.

--
Kirn Gill II
Mobile (SMS only): +1 813-300-2330
VoIP: +1 813-704-0420
Email: segin2005@gmail.com
LinkedIn: http://www.linkedin.com/pub/kirn-gill/32/49a/9a6

On Thu, Aug 1, 2019 at 7:42 PM Kirn Gill <segin2005@gmail.com> wrote:
>
> Replying to Dave Taht,
>
> There's a few considerations here:
>
>  - What is "5G"?
>
> Strictly speaking, 5G is ITU-T's IMT-2020 standard(s). So far, there
> is only one system under this standard, 3GPP's New Radio (NR). NR is
> what is meant as 5G in layspeak.
>
> The NR air interface is defined in 3GPP TS 38.xxx series documents.
>
> Against point 2, about operators simply wanting more active SIMs to
> charge for, it's worth noting that NR can be deployed for private
> operation; the company that's using the service could itself own the
> entire network it's using. There are companies using private LTE
> networks for V2x and remote sensing, see for example:
> https://steelguru.com/mining/l/532247, or contract a third party to
> build a dedicated network:
> https://www.zdnet.com/article/telstra-deploys-private-lte-network-in-png-volcanic-crater-gold-mine/
>
> NR operates over commercial and unlicensed frequency bands. The
> specific frequency bands defined for the system are listed in 3GPP TS
> 38.104 (Rel. 15) section 5.2
>
> 802.11a/b/g/n/ac/ad use CSMA/CA - Carrier Sense Multiple Access with
> Collison Avoidance - as their multiple access scheme, same as 802.3.
> Each transmitter completely owns the medium when transmitting.
>
> 802.11ax, LTE, and NR use OFDMA - Orthogonal Frequency Division
> Multiple Access - as their multiple access scheme. Instead of the
> transmitter having the full channel for the duration it is
> transmitting, OFDMA takes OFDM modulation and divides not only across
> timeslots/timed transmission frames, but also by subdividing the full
> channel into simpler "resource blocks" with a fixed number of OFDM
> tones.
>
> LTE and NR have many features that Wi-Fi lacks which results in a far
> superior user experience. OFDMA, only recently adopted for 802.11ax
> ("Wi-Fi 6"), generally results in far superior throughput rates than
> CSMA/CA when many users are involved. In LTE and NR, this is also
> optimized further with centralized (at the eNB/gNB) MAC scheduling for
> all traffic on both uplink and downlink.
>
> Inter-cell handover in all cellular systems is much better than in
> Wi-Fi; Wi-Fi is a mobile-only system where the mobile station is in
> full control of the process, and it's a "break before make", that is,
> the mobile station fully disassociates from the first access point
> before associating with the next access point, even in the case of a
> shared BSSID and background Ethernet network. It's like unplugging
> from one Ethernet port and plugging into another one rather quickly,
> complete with the brief hiccup in network applications.
>
> Cellular is a lot better; the mobile station scans for neighboring
> cells to the one it's connected to in it's spare time, and sends this
> list to the network, so that the base station can "see" the different
> signal strength's from the mobile station's perspective. The network
> then instructs the mobile station to make a blind jump to whichever
> cell it feels will best serve the mobile station and reduce power
> consumption on that end. "Association" is with the network itself, not
> with individual base stations, so there's no need to do the "break
> before make" dance of Wi-Fi.
>
> --
> Kirn Gill II
> Mobile (SMS only): +1 813-300-2330
> VoIP: +1 813-704-0420
> Email: segin2005@gmail.com
> LinkedIn: http://www.linkedin.com/pub/kirn-gill/32/49a/9a6

Re: [Bloat] Does 5g have the bloat problems of WiFi?

[Kirn Gill]

Replying to Dave Taht,

There's a few considerations here:

 - What is "5G"?

Strictly speaking, 5G is ITU-T's IMT-2020 standard(s). So far, there
is only one system under this standard, 3GPP's New Radio (NR). NR is
what is meant as 5G in layspeak.

The NR air interface is defined in 3GPP TS 38.xxx series documents.

Against point 2, about operators simply wanting more active SIMs to
charge for, it's worth noting that NR can be deployed for private
operation; the company that's using the service could itself own the
entire network it's using. There are companies using private LTE
networks for V2x and remote sensing, see for example:
https://steelguru.com/mining/l/532247, or contract a third party to
build a dedicated network:
https://www.zdnet.com/article/telstra-deploys-private-lte-network-in-png-volcanic-crater-gold-mine/

NR operates over commercial and unlicensed frequency bands. The
specific frequency bands defined for the system are listed in 3GPP TS
38.104 (Rel. 15) section 5.2

802.11a/b/g/n/ac/ad use CSMA/CA - Carrier Sense Multiple Access with
Collison Avoidance - as their multiple access scheme, same as 802.3.
Each transmitter completely owns the medium when transmitting.

802.11ax, LTE, and NR use OFDMA - Orthogonal Frequency Division
Multiple Access - as their multiple access scheme. Instead of the
transmitter having the full channel for the duration it is
transmitting, OFDMA takes OFDM modulation and divides not only across
timeslots/timed transmission frames, but also by subdividing the full
channel into simpler "resource blocks" with a fixed number of OFDM
tones.

LTE and NR have many features that Wi-Fi lacks which results in a far
superior user experience. OFDMA, only recently adopted for 802.11ax
("Wi-Fi 6"), generally results in far superior throughput rates than
CSMA/CA when many users are involved. In LTE and NR, this is also
optimized further with centralized (at the eNB/gNB) MAC scheduling for
all traffic on both uplink and downlink.

Inter-cell handover in all cellular systems is much better than in
Wi-Fi; Wi-Fi is a mobile-only system where the mobile station is in
full control of the process, and it's a "break before make", that is,
the mobile station fully disassociates from the first access point
before associating with the next access point, even in the case of a
shared BSSID and background Ethernet network. It's like unplugging
from one Ethernet port and plugging into another one rather quickly,
complete with the brief hiccup in network applications.

Cellular is a lot better; the mobile station scans for neighboring
cells to the one it's connected to in it's spare time, and sends this
list to the network, so that the base station can "see" the different
signal strength's from the mobile station's perspective. The network
then instructs the mobile station to make a blind jump to whichever
cell it feels will best serve the mobile station and reduce power
consumption on that end. "Association" is with the network itself, not
with individual base stations, so there's no need to do the "break
before make" dance of Wi-Fi.

--
Kirn Gill II
Mobile (SMS only): +1 813-300-2330
VoIP: +1 813-704-0420
Email: segin2005@gmail.com
LinkedIn: http://www.linkedin.com/pub/kirn-gill/32/49a/9a6

[Bloat] Does 5g have the bloat problems of WiFi?

[Kenneth Porter]

I just saw this article claiming that 5g is allowing brick-and-mortar 
automation providers to overcome limitations in WiFi, and I'm wondering if 
the technology is going to suffer from all the same problems previously 
seen in WiFi.

<https://www.zdnet.com/article/googly-eyed-robots-actually-important-5g-edge-computing-benchmark/>

(The "googly-eyed robots" in the title are man-sized robots that wander 
grocery stores to visually track inventory. Someone put googly eyes on them 
to keep them from scaring customers.)