[ Slobodan Milivojevic @ 15.04.2008. 20:49 ] @
Evo kako izgleda kad Telekom napravi ADSL. Od mene do centrale ima nesto oko 2km, i imam Telekom ADSL 1536/192kbps. Kad padne kisa desavaju se cudne stvari, kao to da pri protoku od nesto oko 1024k u downstreamu meni latency ode i do rekordnih 6 sekundi! Koristim huawei MT882 telekomov ruter u pure brigde modu, i komp pod linuxom kao ruter za celu mrezu. On je podesen tako da klasifikuje pakete po source IP-ovima i da limitira protok srazmerno za svaki racunar u zavisnosti od potrosnje, i na njemu mogu da ogranicim ukupan protok kako ja hocu, i time da uradim da latency bude sto manji, tj ovo prakticno znaci da mi link nikad nije do kraja zauzet jer je softverski ogranicen na ruteru.

Ali i pored svega toga evo sta se desava pri protoku u downstreamu od oko 1Mbit/s:

root@gateway:~# ping 79.101.232.1
PING 79.101.232.1 (79.101.232.1) 56(84) bytes of data.
64 bytes from 79.101.232.1: icmp_seq=1 ttl=255 time=4036 ms
64 bytes from 79.101.232.1: icmp_seq=2 ttl=255 time=4131 ms
64 bytes from 79.101.232.1: icmp_seq=3 ttl=255 time=4534 ms
64 bytes from 79.101.232.1: icmp_seq=4 ttl=255 time=4775 ms
64 bytes from 79.101.232.1: icmp_seq=5 ttl=255 time=5064 ms
64 bytes from 79.101.232.1: icmp_seq=6 ttl=255 time=5184 ms
64 bytes from 79.101.232.1: icmp_seq=7 ttl=255 time=5296 ms
64 bytes from 79.101.232.1: icmp_seq=8 ttl=255 time=5373 ms
64 bytes from 79.101.232.1: icmp_seq=9 ttl=255 time=5464 ms
64 bytes from 79.101.232.1: icmp_seq=10 ttl=255 time=5672 ms
64 bytes from 79.101.232.1: icmp_seq=11 ttl=255 time=5772 ms
64 bytes from 79.101.232.1: icmp_seq=12 ttl=255 time=5855 ms
64 bytes from 79.101.232.1: icmp_seq=13 ttl=255 time=5922 ms
64 bytes from 79.101.232.1: icmp_seq=14 ttl=255 time=6000 ms
64 bytes from 79.101.232.1: icmp_seq=15 ttl=255 time=5959 ms
64 bytes from 79.101.232.1: icmp_seq=16 ttl=255 time=6129 ms
64 bytes from 79.101.232.1: icmp_seq=17 ttl=255 time=6155 ms
64 bytes from 79.101.232.1: icmp_seq=18 ttl=255 time=6097 ms
64 bytes from 79.101.232.1: icmp_seq=19 ttl=255 time=6245 ms
64 bytes from 79.101.232.1: icmp_seq=20 ttl=255 time=6339 ms
64 bytes from 79.101.232.1: icmp_seq=21 ttl=255 time=6443 ms
64 bytes from 79.101.232.1: icmp_seq=22 ttl=255 time=6349 ms
64 bytes from 79.101.232.1: icmp_seq=23 ttl=255 time=6517 ms
64 bytes from 79.101.232.1: icmp_seq=24 ttl=255 time=6399 ms
64 bytes from 79.101.232.1: icmp_seq=25 ttl=255 time=6454 ms
64 bytes from 79.101.232.1: icmp_seq=26 ttl=255 time=6445 ms
64 bytes from 79.101.232.1: icmp_seq=27 ttl=255 time=6491 ms
64 bytes from 79.101.232.1: icmp_seq=28 ttl=255 time=6602 ms
64 bytes from 79.101.232.1: icmp_seq=29 ttl=255 time=6530 ms
64 bytes from 79.101.232.1: icmp_seq=30 ttl=255 time=6393 ms
64 bytes from 79.101.232.1: icmp_seq=31 ttl=255 time=5983 ms
64 bytes from 79.101.232.1: icmp_seq=32 ttl=255 time=5491 ms

--- 79.101.232.1 ping statistics ---
37 packets transmitted, 32 received, 13% packet loss, time 36036ms
rtt min/avg/max/mdev = 4036.088/5816.125/6602.205/695.788 ms, pipe 7
root@gateway:~#

Ovo znaci da je link skroz "ugusen" pri protoku od samo 1Mbit/s i to me opasno nervira, jednostavno na 6 racunara delim ovaj net i ne mogu da kazem drugima da ne koriste net kako bi ja mogao da ga koristim... Ranije je maksimalni ping pri protoku od 1350kbps bio oko 250ms sto je podnosljivo. U zadnje vreme tako lose radi da je to nemoguce.

Cisto poredjenja radi, pogledajte kako ista konfiguracija ruter racunara radi na exe-net wireless-u 1536/384kbps pored aktivnih torrenta:
root@gateway:~# ping 92.60.224.4
PING 92.60.224.4 (92.60.224.4) 56(84) bytes of data.
64 bytes from 92.60.224.4: icmp_seq=1 ttl=64 time=4.32 ms
64 bytes from 92.60.224.4: icmp_seq=2 ttl=64 time=3.26 ms
64 bytes from 92.60.224.4: icmp_seq=3 ttl=64 time=3.58 ms
64 bytes from 92.60.224.4: icmp_seq=4 ttl=64 time=2.40 ms
64 bytes from 92.60.224.4: icmp_seq=5 ttl=64 time=7.86 ms
64 bytes from 92.60.224.4: icmp_seq=6 ttl=64 time=13.1 ms

--- 92.60.224.4 ping statistics ---
6 packets transmitted, 6 received, 0% packet loss, time 5037ms
rtt min/avg/max/mdev = 2.400/5.772/13.195/3.741 ms

Evo shot-a sa Huawei modema/rutera. I prema recima ljudi sa 0800 100 100 Attenuation previse velik i da se zato javljaju navedeni problemi:

[att_img]

Doduse obecali su da ce me kontaktirati i da je problem prijavljen, pa cemo videti. U svakom slucaju, jedva upotrebljiv internet za 2800 dinara mesecno!
[ Slobodan Milivojevic @ 16.04.2008. 00:30 ] @
vrlo interesantna stvar kad se telnetujem na Huawei dobijam sledece:
$get atm port

If-Name : atm-0 MaxVccs : 8
CBRPriority : 5 UBRPriority : 1
RTVBRPriority : 4 NRTVBRPriority : 3
GFRPriority : 2 Latency : Interleaved
MaxConfVccs : 3
OAMSrc : 0xffffffffffffffffffffffffffffffff
Oper Status : Up Admin Status : Up

Latency: Interleaved

A na web interfejsu pise Fast... Sta je ovde tacno?
[ Slobodan Milivojevic @ 17.04.2008. 11:28 ] @
I kako je sad Attenuation jos veci a niko nista nije dirao?

[ Ivan Dimkovic @ 17.04.2008. 11:37 ] @
Pa ocigledno imas jako los kvalitet bakarnog voda koji varira sa vremenskim uslovima.

Trazi od Telekoma da te stave na neku drugu paricu, ako je to moguce i ako postoje neke druge parice koje imaju bolji kvalitet.

Citat:

--- 79.101.232.1 ping statistics ---
37 packets transmitted, 32 received, 13% packet loss, time 36036ms
rtt min/avg/max/mdev = 4036.088/5816.125/6602.205/695.788 ms, pipe 7
root@gateway:~#


Ovo je abnormalno veliki delay - vidim da imas Fastpath ukljucen, mozda bi bilo pametnije da Telekom ukljuci interleaving za tebe, to bi povecalo minimalnu latenciju ali bi verovatno umanjilo greske.
[ Slobodan Milivojevic @ 17.04.2008. 18:38 ] @
Evo kupio sam TP-Link 8810A ADSL ruter i stanje je sada ovakvo:

64 bytes from 79.101.149.1: icmp_seq=124 ttl=255 time=483 ms
64 bytes from 79.101.149.1: icmp_seq=125 ttl=255 time=273 ms
64 bytes from 79.101.149.1: icmp_seq=127 ttl=255 time=110 ms
64 bytes from 79.101.149.1: icmp_seq=128 ttl=255 time=120 ms
64 bytes from 79.101.149.1: icmp_seq=129 ttl=255 time=141 ms
64 bytes from 79.101.149.1: icmp_seq=130 ttl=255 time=198 ms
64 bytes from 79.101.149.1: icmp_seq=131 ttl=255 time=225 ms
64 bytes from 79.101.149.1: icmp_seq=132 ttl=255 time=219 ms
64 bytes from 79.101.149.1: icmp_seq=133 ttl=255 time=192 ms
64 bytes from 79.101.149.1: icmp_seq=134 ttl=255 time=181 ms
64 bytes from 79.101.149.1: icmp_seq=135 ttl=255 time=163 ms
64 bytes from 79.101.149.1: icmp_seq=136 ttl=255 time=165 ms
64 bytes from 79.101.149.1: icmp_seq=137 ttl=255 time=243 ms
64 bytes from 79.101.149.1: icmp_seq=138 ttl=255 time=410 ms
64 bytes from 79.101.149.1: icmp_seq=139 ttl=255 time=624 ms
64 bytes from 79.101.149.1: icmp_seq=140 ttl=255 time=834 ms
64 bytes from 79.101.149.1: icmp_seq=141 ttl=255 time=1012 ms
64 bytes from 79.101.149.1: icmp_seq=142 ttl=255 time=1226 ms
64 bytes from 79.101.149.1: icmp_seq=143 ttl=255 time=1405 ms
64 bytes from 79.101.149.1: icmp_seq=144 ttl=255 time=1589 ms
64 bytes from 79.101.149.1: icmp_seq=145 ttl=255 time=1686 ms
64 bytes from 79.101.149.1: icmp_seq=146 ttl=255 time=1891 ms
64 bytes from 79.101.149.1: icmp_seq=147 ttl=255 time=2017 ms
64 bytes from 79.101.149.1: icmp_seq=148 ttl=255 time=2307 ms
64 bytes from 79.101.149.1: icmp_seq=149 ttl=255 time=2434 ms
64 bytes from 79.101.149.1: icmp_seq=150 ttl=255 time=2647 ms
64 bytes from 79.101.149.1: icmp_seq=151 ttl=255 time=2601 ms
64 bytes from 79.101.149.1: icmp_seq=152 ttl=255 time=2095 ms
64 bytes from 79.101.149.1: icmp_seq=153 ttl=255 time=1797 ms
64 bytes from 79.101.149.1: icmp_seq=154 ttl=255 time=1719 ms
64 bytes from 79.101.149.1: icmp_seq=155 ttl=255 time=1470 ms
64 bytes from 79.101.149.1: icmp_seq=156 ttl=255 time=514 ms
64 bytes from 79.101.149.1: icmp_seq=157 ttl=255 time=95.0 ms
64 bytes from 79.101.149.1: icmp_seq=158 ttl=255 time=18.6 ms
64 bytes from 79.101.149.1: icmp_seq=159 ttl=255 time=298 ms
64 bytes from 79.101.149.1: icmp_seq=160 ttl=255 time=747 ms
64 bytes from 79.101.149.1: icmp_seq=161 ttl=255 time=1204 ms
64 bytes from 79.101.149.1: icmp_seq=162 ttl=255 time=1657 ms
64 bytes from 79.101.149.1: icmp_seq=163 ttl=255 time=2063 ms
64 bytes from 79.101.149.1: icmp_seq=164 ttl=255 time=2361 ms
64 bytes from 79.101.149.1: icmp_seq=165 ttl=255 time=1949 ms
64 bytes from 79.101.149.1: icmp_seq=166 ttl=255 time=1395 ms
64 bytes from 79.101.149.1: icmp_seq=168 ttl=255 time=1865 ms
64 bytes from 79.101.149.1: icmp_seq=169 ttl=255 time=2271 ms
64 bytes from 79.101.149.1: icmp_seq=170 ttl=255 time=2623 ms
64 bytes from 79.101.149.1: icmp_seq=171 ttl=255 time=2584 ms
64 bytes from 79.101.149.1: icmp_seq=172 ttl=255 time=2614 ms
64 bytes from 79.101.149.1: icmp_seq=173 ttl=255 time=2627 ms
64 bytes from 79.101.149.1: icmp_seq=174 ttl=255 time=2430 ms
64 bytes from 79.101.149.1: icmp_seq=175 ttl=255 time=2233 ms
64 bytes from 79.101.149.1: icmp_seq=176 ttl=255 time=1867 ms
64 bytes from 79.101.149.1: icmp_seq=177 ttl=255 time=1325 ms
64 bytes from 79.101.149.1: icmp_seq=178 ttl=255 time=1644 ms
64 bytes from 79.101.149.1: icmp_seq=179 ttl=255 time=2132 ms
64 bytes from 79.101.149.1: icmp_seq=180 ttl=255 time=2266 ms
64 bytes from 79.101.149.1: icmp_seq=181 ttl=255 time=2182 ms
64 bytes from 79.101.149.1: icmp_seq=182 ttl=255 time=2358 ms
64 bytes from 79.101.149.1: icmp_seq=183 ttl=255 time=2246 ms
64 bytes from 79.101.149.1: icmp_seq=184 ttl=255 time=2143 ms
64 bytes from 79.101.149.1: icmp_seq=185 ttl=255 time=1933 ms
64 bytes from 79.101.149.1: icmp_seq=186 ttl=255 time=1950 ms
64 bytes from 79.101.149.1: icmp_seq=187 ttl=255 time=1455 ms
64 bytes from 79.101.149.1: icmp_seq=188 ttl=255 time=1567 ms
64 bytes from 79.101.149.1: icmp_seq=189 ttl=255 time=1724 ms
64 bytes from 79.101.149.1: icmp_seq=190 ttl=255 time=1546 ms
64 bytes from 79.101.149.1: icmp_seq=191 ttl=255 time=1001 ms
64 bytes from 79.101.149.1: icmp_seq=192 ttl=255 time=892 ms
64 bytes from 79.101.149.1: icmp_seq=193 ttl=255 time=693 ms
64 bytes from 79.101.149.1: icmp_seq=194 ttl=255 time=386 ms
64 bytes from 79.101.149.1: icmp_seq=195 ttl=255 time=335 ms
64 bytes from 79.101.149.1: icmp_seq=196 ttl=255 time=200 ms
64 bytes from 79.101.149.1: icmp_seq=197 ttl=255 time=192 ms
64 bytes from 79.101.149.1: icmp_seq=198 ttl=255 time=198 ms
64 bytes from 79.101.149.1: icmp_seq=199 ttl=255 time=161 ms
64 bytes from 79.101.149.1: icmp_seq=200 ttl=255 time=178 ms

Protok je oko 1200kbps. Ali ipak su prevelike oscilacije... Kako moze 160-200ms u jednom trenutku, a posle 10sec 2000+ms?
Evo shota sa tog rutera:
[att_img]
[ bobe84 @ 17.04.2008. 21:27 ] @
Danas sam zvao telekom tehnicku podrsku po treci put i ljubazna devojka mi rece da ima u evidenciji da sam vec dva puta prijavljivao kvar/smetnju i da njoj pise da je to vec DVA puta otklonjeno.
Meni su u tehnickoj podrsci rekli da ce me kontaktirati u vezi kvara, al ipak nisu...

Saobracaj je ogranicen u downstreamu na CITAVIH 1024kbit, i sada jos uvek latency varira od 20 do 1000ms. Inace modem bez limita skida ~ 133kb/s
Mene samo zanima da li je jos neko imao ovakvih problema i ako jeste kako ih je resavao.
Vec sumnjam u tu njihovu tehnicku podrsku i mislim da me nece niko ni zvati kad vec 3 dana nisu.
Sta bi sa onih famoznih 1.5mbit/s il je to samo reklama i obmana kao i kod svih ostalih reklama i ponuda. Ups sad se tek setih da zivim u Srbiji...

Toliko o adsl-u u Srbiji, izgleda da se kod nas sve mora raditi na tezi nacin a ne na sto laksi i jednostavniji nacin.
[ mobilexpert @ 22.04.2008. 06:56 ] @
@Slobodan

lepo su ti ljudi rekli ... veza do DSLAM-a u centrali ti je OCAJNA,
modem samo sto se ne zapali od pokusaja da pojaca signal i popravi greske.

ja sam iz paranoje adsl spliter stavio u ptt kutiju u dnu zgrade, zajedno sa modemom
i odatle sproveo lan do mikrotika koji mi drzi PPPoE konekciju i lokalnu mrezu ...

da se ne ubedacis ... ali pojacanje mi je 1dB downstream, 1.5dB upstream
test iz modema pokazuje da mogu da proguram skoro 28mbps downstream-a i nesto vise od 1.4mbps upstreama
naravno, ima veze sto mi je nova centrala na oko ~400m udaljenosti
i sto su prosle godine postavljali nove kablove do moje zgrade

e sad, ona prica o pingu, dok imas 1mbps download saobracaja ...
ADSL je ASinhroni servis, pa cak i da imas 512k upload, opet bi ti varirao ping pri malo vecem downloadu,
to nije frame relay ili wireless servis, gde podaci istovremeno (sinhrono) odlaze i dolaze do tebe.

ima pod mikrotikom fora, da odrzis koliko-toliko kulturan ping (ispod 100ms ka inostranstvu) sa do max. 50% download kapaciteta.

zovi ... maltretiraj, kazi da ces da otkazes adsl servis i da ih tuzis ... da vidis
kako ce narednog dana da se pojave monteri iz telekoma i da pocnu da "cesljaju" i ciste tvoju liniju (paricu).

samo cvrsto i ostro !


poz.
ALeksandar.
[ bobe84 @ 22.04.2008. 15:05 ] @
@Aleksandar
Mozesh li malo da pojasnis za tu foru u MT-u?
[ knjaz_milos @ 22.04.2008. 19:19 ] @
@Slobodan

Mislim da ljudi ne vole to da rade ali da li si probao da stavis samo jedan racunar direktno na TP link (Huawei) i onda propinguj...pa vidi kakvo je tada stanje.

Ciljam na to da je ta korisnicka ADSL oprema ipak entry level i da pod velikim opterecenjem verovatno dolazi do shtucanja,chudo i da ti nije dropovao neki paket.Probaj test 1 na 1 (pc na adsl ruter direktno) ... izbacis sve ostalo iz priche,pa ako je i tako ista stvar (da je packet return time isto jako velik) onda je definitivno do linije,telekom ima odgovornost za kvalitet do pocetka kucne instalacije (postanski ormaric u zgradi,kuci) tako da ako si siguran da tu nema loshih kontakata i spojeva koji mogu da utichu na slabljenje...onda zovi telekom.Oni kad ispituju da li je sve ok,oni nakace svoj modem ali direkt na centrali...na portu...ne mogu da provere spojni put....tu trasu bakarnu shto ide do tebe.Ali duzhni su da ako se problem ne reshi i to da istestiraju...bukvalno da dodju kod tebe i da izvrse merenja sa svojom opremom odatle.

@mobilexpert

Kako to ? Kakva je to centrala,kakvu opremu imash ? Zar ADSL 2+ ne ide max do 24Mbps za download i 1 Mbps za upload ? Kako se tvoj ruter kachi na vishe vrednosti nego shto standard propisuje ? Please explain ... zaista me interesuje.
[ mobilexpert @ 28.04.2008. 01:48 ] @
@bobe84 .... promenis tip Queue-a pod interface queue ... stavis wireless-default

@knjaz_milosh ... stavili su ove godine novu centralu na 300m od moje zgrade,
a ja iz paranoje jos stavio spliter u ptt-kutiju u dnu zgrade, plus preko toga sam LEMIO sve kablove,
tako da sam izvukao da mi modem ima pojacanje po 1-1,5dB u oba smera ...
i kad sam uradio test iz modemovog cli-ja, pokazao je mogucu propusnu moc od ~26.8mbps/1.x Mbps
(odavno vec stoji na bridge pa me mrzi da ga gledam, ali uskoro stavljam tp-linkov modem, pa cu ponoviti da ti napisem tacne vrednosti)

poz.
Alexandar
[ Ivan Dimkovic @ 28.04.2008. 07:20 ] @
Citat:

Zar ADSL 2+ ne ide max do 24Mbps za download i 1 Mbps za upload ?


Ide, a za to mu treba nekih 27-28 Mbps "raw" saobracaja ;-)