Last week's announcement of a new lower-cost DAP-1522 dual-band draft 802.11n AP/bridge from D-Link could bring dual-band draft 11n within the reach of more consumers. Although it lists for $119.99, at least one online retailer is already advertising a price under $100. So I hit the FCC ID filings to see how D-Link managed to knock $100 off the list price of the 1522's predecessor, the DAP-1555.
Both use Ubicom processors (which provide their automatic uplink QoS features), Atheros mini-PCI radio modules and include 4 port switches. The 4500's is gigabit (via a Realtek RTL8356), while the 1555's is 10/100, provided by a Marvell 88E6061.
Figure 1: DAP-1555 inside
But the 1522 is based on an entirely different platform (Figure 2), using both a Ralink SoC processor (RT2880F), which includes the draft 11n MAC / Baseband processing, and dual-band draft 802.11n 2T3R (2 transmit, 3 receive channels) transceiver (RT2850L). The 1522 has a four-port gigabit switch, which comes from a Realtek RTL8366, instead of the 1555's 10/100 switch.
Figure 2: DAP-1522 board
One of the advantages of the Ubicom processors is the StreamEngine automatic QoS feature, which automatically classifies packets flowing through the router (or in this case, bridge), giving priority to audio and video streams. Figure 3 shows the 1555's WISH (Wireless Intelligent Stream Handling) controls.
Figure 3: DAP-1555 WISH (auto QoS)
D-Link appears to not be ready to give up automatic QoS with its switch to Ralink. Figure 4 shows the QoS configuration page from the DAP-1522's manual, which appears to also have an Automatic setting. It will be interesting to see how automatic Ralink's QoS really is.
Figure 4: DAP-1522 QoS
Maybe breaking the $100 price barrier is D-Link's way of getting consumers' minds off the continued unavailability of dual-band dual-radio DIR-855, which, if it ever ships, will cost almost 3 times as much. At any rate, I've asked D-Link for a DAP-1522 for review, so that I can see if it will be a decent way for you to upgrade to dual-band draft 11n.