The DIR-655 router belongs to the new Xtreme N family which features the most advanced network processors. Here, the PCB carries a communications and media processor (CMP) from Ubicom’s StreamEngine 5000 series. Featuring a unique architecture, these processors are superior to similar processors with other architectures, at least in their manufacturer’s eyes. The DIR-655 comes with the junior processor model marked as IP5160 which delivers as much performance as modern processors with MIPS and ARM architectures do (according to Ubicom). The manufacturer’s website offers a document that contains a detailed performance analysis of CMPs with different architectures. Here are a couple of tables demonstrating the superiority of StreamEngine 5000 processors:
Overall performance
Routing performance
A key feature of IP51xx processors that gives them the edge in terms of performance is that they have integrated memory besides just cache. Every data packet passes through this integrated memory and is processed much faster.

The exact specifications of the IP5160 are as follows (quoted from the Ubicom website):

Feature | StreamEngine 5160 |
Sustained Performance | ~250+ Mbps |
Number of Independent Threads | 10 |
RAM Type | DDR1/2 16-bit-wide |
External RAM | 2 Gb |
General I/O | PCI, PLIO, USB 2.0 (FS/HS), USB 2.0 (HS) |
Ethernet (2 Ports) | 10/100/1000 |
Networking I/O | MII (2), RMII (2), RGMII |
Hardware Encryption / | DES/3DES, AES, SHA-1, MD5, RSA, |
Media I/O | IDE, AC97, I2 S, Utopia, MPEG TS, YUV |
VoIP | G.711, G.726, G.729AB, |
Audio Processing | MP3, AAC, WMA, WMA9 |
The specs are impressive indeed. The DIR-655 doesn’t make use even of half of the processor’s capabilities!



