M40

From JuniperClue

Juniper M40 Router

FPC/PIC Slots	8 FPC, 32 PIC
Agg. Bandwidth	25.6 Gbit/s
FPC Types	type-1
PIC Style	P-style
Power Supplies	2 (1+1 redundant)
Switch Board	SCB (non-redundant)
Release date	September 16, 1998

The Juniper M40 (Codename: Martini) was Juniper's first shipping product. Although it has been end of lifed and replaced with the M40e, it is still widely used in many networks.

Innovations

Physical

The M40 is a rack-mount unit 35" (20U) in height. The system can contain up to eight FPCs, and each FPC can contain up to four type-1 PICs with P-style mechanicals.

Power

Both AC and DC power supplies are available for the M40. The maximum system power draw for a fully loaded configuration is around ?? watts. The AC supply supports input voltages in the range of ?? volts, while the DC supply supports from ?? volts.

Cooling

Craft Interface

Routing Engine

The M40 originally shipped with RE-1.0 (P2 233MHz, 256MB). The M40 is the only JunOS platform with a half-duplex ethernet connection between the RE and the PFE.

Forwarding

The M40 uses an ASIC based forwarding path which offers better than 40 million packets per second in lookup performance. The M40 initially shipped with the original Internet Processor ASIC but was later upgraded to the Internet Processor II. The forwarding architecture of the M40, called the Martini architecture, was reused directly on many of Juniper's later routers such as the M20, M5, and M10, and with some modification in the M160 and the M40e.

Unlike the other Martini architecture routers, the A-Chips of the M40 are installed on the backplane rather than on a removable card. Later Juniper products have far fewer active components on their midplanes and backplanes. The balance of the packet forwarding engine is contained on the SCB.

Hot Swapping

Like the M20, an entire FPC must be disabled and removed to swap a single PIC, which requires the interruption of three unrelated PICs and is considered an annoyance. This is due entirely to mechanical considerations, as the PICs themselves are capable of being hot-swapped as long as they have been previously disabled in software (no Craft offline button exists). On later models, Juniper made mechanical changes which make it easy to PIC hotswap.