Cisco 4000 - Manual (Page 9)

Overview of the Cisco 4000 Series Routers 1-9
Memory Systems
Table 1-3 Cisco 4000 Series Processor and Memory Specifications
Memory Systems
The Cisco 4000 series memory systems (see Figure 1-2) have the following functions:
•
Main memory—Stores the running configuration and routing tables. The Cisco IOS
software executes from main memory.
•
Shared memory—Used for packet buffering by the router’s network interfaces.
•
Flash memory—Stores the operating system software image. In the Cisco 4500-M and
4700-M, the Flash memory also stores the boot helper software.
•
NVRAM—Stores the system configuration file and the virtual configuration register.
•
Boot EPROM—In the Cisco 4000-M, erasable programmable read-only memory
(EPROM)-based memory stores the boot helper—a subset of the Cisco IOS
software—and the ROM monitor. In the Cisco 4500-M and Cisco 4700-M, only the
ROM monitor is EPROM based. The boot helper image allows you to boot the router
Description Cisco 4000-M Cisco 4500-M Cisco 4700-M
Processor 40-MHz Motorola
68EC030 100-MHz IDT Orion
RISC
1
1. The Orion microprocessor is based on the MIPS R4400 and is pin-compatible.
133-MHz IDT Orion
RISC
Main memory
(DRAM)
2
2. DRAM = dynamic random-access memory.
4, 8, 16, or 32 MB 8, 16, or 32 MB 16, 32, or 64 MB
Secondary cache
memory None None 512 KB
Shared memory
(DRAM) 4 or 16 MB 4, 8, or 16 MB 4, 8, or 16 MB
Flash memory 4 or 8 MB 4, 8, 16, 32, or 64 MB 4, 8, 16, 32, or 64 MB
NVRAM
3
3. NVRAM = nonvolatile random-access memory.
128 KB 128 KB 128 KB
Boot ROM 128 KB–8 MB 128–512 KB 128–512 KB
Boot Flash Not available 4–16 MB 4–16 MB