The Cisco 3900 Series is four routers: the 3925, 3945, 3925E and 3945E. They differ mainly in service-module slot count and in the Services Performance Engine, or SPE, the field-replaceable board that holds the route processor. The 3925 ships with the SPE100 and the 3945 with the SPE150. The 3925E uses the SPE200 and the 3945E the SPE250. Every model arrives with IP Base, 256 MB of Compact Flash and 1 GB of DRAM.
Slot counts follow the model. The 3925 and 3945 have three Gigabit Ethernet ports and four EHWIC slots with four DSP slots, while the E models have four Gigabit Ethernet ports, three EHWIC slots and three DSP slots. Service-module slots are two on the 3925 and 3925E and four on the 3945 and 3945E. The SPE250 and SPE150 fit 3945 platforms only, and the SPE200 and SPE100 fit 3925 platforms only. The spare C3900-SPE150/K9 belongs in a 3945.
The 1 GB of default DRAM is two 512 MB DIMMs. Both slots must hold matching modules, and the router does not accept different sizes or a single DIMM. Factory upgrades reach 2 GB or 4 GB, and spares come as MEM-3900-512MB= and MEM-3900-1GB.
Each router takes two power supplies, set up for redundancy or for extra PoE power. AC, PoE and DC supplies can be mixed in any pairing. PWR-3900-AC and PWR-3900-POE are sold with the system or as spares, and a PoE supply needs a C15-rated power cord. To power ports on a switch module inside the router, the router must be ordered with a PoE supply.
Compact Flash slot 0 holds the 256 MB card, and a second slot takes an optional card; the MEM-CF parts are shared with the 1900 and 2900 Series. The standard fan assembly is 3900-FANASSY. 3900-FANASSY-NEBS is the alternate, with an air filter for dusty or NEBS sites, and RPS-COVER-3900= covers an empty second power supply slot.
For console access, CAB-CONSOLE-USB is a 6 ft cable with USB Type A and mini-B ends, and CAB-CONSOLE-RJ45 runs from RJ45 to DB9F. Single-model detail for the 3945 is on the Cisco 3945 page. More routers sit in the Cisco router category, and networking leads on to the other families.
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Cisco 3900 Series Routers parts we supply
Routers and engines (8)
- CISCO3925/K9: 3925 with SPE100, 3GE, 4 EHWIC, 4 DSP, 2 SM, 256 MB flash, 1 GB DRAM, IP Base
- CISCO3945/K9: 3945 with SPE150, 3GE, 4 EHWIC, 4 DSP, 4 SM, 256 MB flash, 1 GB DRAM, IP Base
- CISCO3925E/K9: 3925E with SPE200, 4GE, 3 EHWIC, 3 DSP, 2 SM, 256 MB flash, 1 GB DRAM, IP Base
- CISCO3945E/K9: 3945E with SPE250, 4GE, 3 EHWIC, 3 DSP, 4 SM, 256 MB flash, 1 GB DRAM, IP Base
- C3900-SPE100/K9=: Services Performance Engine 100 for the 3925, spare
- C3900-SPE150/K9=: Services Performance Engine 150 for the 3945, spare
- C3900-SPE200/K9=: Services Performance Engine 200 for the 3925E, spare
- C3900-SPE250/K9=: Services Performance Engine 250 for the 3945E, spare
Power supplies (6)
- PWR-3900-AC: AC power supply, system and spare
- PWR-3900-AC/2: AC power supply, secondary, system only
- PWR-3900-POE: AC power supply with Power over Ethernet, system and spare
- PWR-3900-POE/2: AC power supply with Power over Ethernet, secondary, system only
- PWR-3900-DC: DC power supply, system and spare
- PWR-3900-DC/2: DC power supply, secondary, system only
Memory (2)
- MEM-3900-512MB=: 512 MB DRAM, spare
- MEM-3900-1GB=: 1 GB DRAM, spare
Fans, covers and cables (5)
- 3900-FANASSY: Fan assembly, system and spare
- 3900-FANASSY-NEBS: NEBS fan assembly with filter and bezel
- RPS-COVER-3900=: Cover for an empty second power supply slot
- CAB-CONSOLE-RJ45: 6 ft console cable, RJ45 to DB9F
- CAB-CONSOLE-USB: 6 ft console cable, USB Type A to mini-B