Ruckus wireless has broken the wireless bridge price/performance barrier with the release of the new Ruckus 7731 Outdoor 802.11n wireless bridge. Each end has Ruckus’s integrated smart antenna array which which offers a 14 dbi gain with 30 degree beam width. While not the strongest antenna in its class and has a bit too wide of a beam width for most (Ruckus says they are working on this) the 7731 does get some pretty good distance. Here are some “real world” numbers that ruckus is boasting.
- Up to 190 Mbps at 1.5 km/1 mi
- Up to 165 Mbps at 3 km/2 mi
- Up to 100 Mbps at 5 km/3 mi
- Up to 50 Mbps at 10 km/6 mi
- 15km maximum range
Aside from the speed the 7731 also has some other cool & handy features to help ease installation like the ability to find its peer automatically, LED based aiming technology, IP65 rating, lightweight design (1.93lbs) and easy 802.3af POE support.
I didn’t find any mention of latency in the 7731 documentation which is an important number when dealing with voice & video. So, while on a conference call with Ruckus yesterday discussing how to effectively use their platform for 3G offload (different post) and asked about the 7731′s latency. The engineer on the call was not sure but this morning I got a detailed explanation and was impressed! Here is the email from the Ruckus engineer…
Right now I am pinging over a 10km setup, I see rtt min/avg/max/mdev = 0.663/0.986/1.557/0.271 ms
The packet transmission time on the link depends on the link condition, traffic patterns (sizes of packets, and burstiness of packets). A typical full size packet takes about 200us on highest rate to a couple of ms on lowest rate. If consider aggregation, the per aggregate time varies even more depending on the aggregation size, link speed…
We passed voice testing with 20km setup in China, as GSM backhaul, achieving good MOS score with an actual voice call.
Notice those latency stats. You are looking at under ~2ms for a 10Km link. These are the numbers we normally see on Motorola PTP 500/600s. I really love the fact that Ruckus is so into their product that they will actually ping across a production link to get you the information you need.
OK, so finally on to the barrier breaking price…The Ruckus 7731 is $2398 for the pair (yes for both!). Assuming their numbers are correct and you are looking at a short hop that is ~$13 per Mbps!
I do concede that this is a wifi based product and you will not see any of the special NLOS features you get from Motorola PTP series point to points but for relatively short LOS hops this bridge rocks!