Abstract

3Com Corporation commissioned The Tolly Group to conduct an evaluation of branch office connectivity using NETBuilder Remote Office (NBRO) routers. To accomplish this task, The Tolly Group designed a typical branch office network and then built the network using NBRO routers. Tests show the NBRO routers deliver solid performance, are easy to install, and offer flexible and cost effective deployment options for small, branch office configurations. Tests involved frame relay and real-time data compression. 

Tolly Group Report #5275 (June 1995) evaluates 3Com NETBuilder Remote Office (NBRO) routers for branch-office connectivity, measuring performance with and without WAN compression and assessing ease of deployment using 3Com’s Boundary Routing approach .

Performance

• Without compression, NBRO forwarded IP over the WAN at 53 Kbit/s with 64-byte frames and 63 Kbit/s with 1,500-byte frames, demonstrating efficient use of low-speed links .

• With Frame Relay compression enabled, results included 7.7:1 at 1,500-byte frames and 4.5:1 at 512-byte frames; 64-byte frames stayed near wire speed as expected for minimally compressible data .

• Anti-expansion logic functioned correctly; 512-byte pre-compressed (“zipped”) frames passed at wire speed with an effective ≈1:1 ratio, avoiding needless processing overhead .

Ease of use and remote operations

• Boundary Routing let the branch router auto-detect Frame Relay, line speed, and DLCI, learn its IP address from the central site, and come online with no on-site configuration beyond cabling .

• Central IT could push code updates over the WAN; dual images in NVRAM protected the branch from failed-update outages, and admins managed the device remotely via Telnet .

Deployment flexibility

• The NBRO 227 runs the same code base as NETBuilder II with fewer interfaces and lower cost, and can support up to ten branch offices in a Frame Relay hub-and-spoke design, providing a cost-effective option for small sites that still need full routing features .

Bottom line: NBRO routers deliver solid performance on low-speed links, strong compression with proper anti-expansion behavior, simple zero-touch branch turn-up, and centralized maintenance, making them well suited for economical branch-office connectivity without sacrificing manageability or reliability .