Broadcom BCM4908 Router SoC Supports 2.5 Gigabit Ethernet, and Up to 3.4 Gbps Combined WiFi Speeds

[maurer]

The BCM4908 processor includes a 28nm 1.8GHz ARM CPU alongside Broadcom’s network packet processor to deliver more than 5 Gbits/second of system data throughput without taxing the CPU. The CPU would be left free to run a variety of software on the router, the company says.
The chip also supports the increased speeds coming into the home through services such as Google Fiber using an interface for a 2.5 Gigabit/s Ethernet PHY. Broadcom officials said routers can achieve over 3.5 Gbits/s combined speed when paired with the company’s wave2 5G WiFi MU-MIMO chip.
Additionally, the router processor supports tri-band 802.11ac MU-MIMO Wi-Fi – three BCM4366 4x4 radios, each with an integrated CPU for host offload processing – to provide seven CPU cores with more than 9.6 GHz of CPU compute power.
By leaving the router CPU free from Wi-Fi processing, Broadcom expects its offering to go beyond smart home and enterprise to network attached storage. The company did not announce partner companies for its silicon, but said BCM4908 is currently shipping and will be in mass production at the end of the second quarter of 2016.

via http://www.eetimes.com/document.asp?doc_id=1328558

 

[kvic]

Sounds like a truly next gen all-in-one router platform.

Quoting from Internet...

• Quad core 64-bit ARM processor @ 1.8 GHz
• Zero CPU Wi-Fi offload to free up CPU resources
• BroadStream iQoS acceleration
• Dedicated security processor to enable hardware VPN acceleration
• 2.5Gb Base-X Ethernet WAN/LAN port for supporting fast connectivity to multi-gigabit modem or a Network Attached Storage (NAS) device
• Peripherals – Integrated SATA III, two USB 3.0 ports and three PCIe Gen 2 ports
• Low power – 28nm processor technology and advanced power management for more than 50% percent power usage reduction compared to previous solutions
• Support for Broadcom’s tri-band (AC5300) 5G WiFi XStream 802.11ac MU-MIMO with:
  • 3x BCM4366 4×4 radios, each with an integrated CPU for host offload processing
  • Providing a total of seven CPU cores (“Septacore”) with more than 9.6 GHz of CPU horse power
• Hardware acceleration for routing and USB storage

 

[pege63]

It wont bring any differences witch Router you have , what you need is a router that is fast as the speed of the clients that you have in your home.

 

[kvic]

You may say so. Wireless upgrade is done in AC88/AC5300. This upgrades the other half - the main SoC. People have been complaining about BCM4708/9 used for ages without a true upgrade.

BC4908 seems answering the call.

 

[avtella]

Seems nice. I wonder what core its using, Cortex A35 or A53? If so, it will be slower, in terms of IPCs, than the A9 in the 470X or A15 in the Qualcomm chipsets, but 4x cores should make up for that easily.

Edit: Seems it is Cortex A53 so almost close (slighly less) to the A9 in terms of performance per Mhz.

 

[System Error Message]

I hate when they mention more cores than it really has. A CPU meant for accelerating tasks like wifi that cannot do anything else shouldnt be considered a core. Its like saying having a PC with 4 CPU cores and a high end GPU with 32 cores means having a 36 core PC, ridiculous because you cant run normal code on the GPU. There really needs to be a law against this sort of false advertising. Until those extra CPUs used in accelerating certain tasks are capable of working with the CPU in running software or code than it cannot be considered a core in the main product itself. So if i had a soundcard with a CPU and a quad core CPU in my PC does it make my PC a pentacore? NO!.

 

[avtella]

Yeah, I agree with you on that, I remember when they first announced the XStream chipset they said 5 cores and 2.96 Ghz processing power.... Not to mention performance per mhz is probably much lower on the Cortex R7 or whatever the off load cores are, not that it matters much but still lol.

 

[kvic]

I agree with the sentiment in general. Marketing speak need not to take it seriously. lol

Time to refresh memory of performance boost from A53 over A7, AES operations are insanely faster. http://www.anandtech.com/show/8718/the-samsung-galaxy-note-4-exynos-review/4

Also with a brand new SoC, hopefully the linux kernel in home routers will eventually get an upgrade from the good old but ancient 2.6.36.

 

[System Error Message]

i will have to say this again, they should've used the A57. Since they do power saving poorly on networking theres no harm in using the A57.

 

[avtella]

With the A57 you would need a much better cooling solution especially at 28nm and also a much bigger die, multiple A53s can fit in the same area as one A57 if I'm not mistaken. From a price, yield and performance to power ratio point the A53 is probably better. Considering consumer networking usually survives on much thinner margins than mobile companies it may not be worthwhile to make extra accommodations necessary for the A57.

 

[kvic]

For home use, most of the time the router is idle (except those doing torrent 24/7). Bandwidth demand is bursty and hence the router's workload. As long as aggregate traffic within LAN and into WAN is not constantly above 500Mbit/s, dual-core cortext A9 is actually sufficient. Newer models such as RT-AC88 already has dedicated WiFi chips to offload main processor i.e. the bullet point "Zero CPU Wi-Fi offload to free up CPU resources". So expect cortex A9 to stay for a much longer period than the announcement may want ppl to imagine otherwise.

With two more cores and a 64bit architecture plus various hardware accelerators, this is a huge upgrade. A53 or A57 doesn't matter much to me, I would opt for the one wasting less electricity. Not to mention that, under current WRT firmware, routing is concentrated on one core, you'll have three idle cores for many interesting apps. That's more than enough power IMO for a very demanding home network.

 

[randomName]

This is an interesting thread. Learned a little bit from it

 

[sfx2000]

eems nice. I wonder what core its using, Cortex A35 or A53? If so, it will be slower, in terms of IPCs, than the A9 in the 470X or A15 in the Qualcomm chipsets, but 4x cores should make up for that easily.

Edit: Seems it is Cortex A53 so almost close (slighly less) to the A9 in terms of performance per Mhz.

The Broadcom B53 a variant of Cortex-A53... from a SW perspective, it's different enough to treat it alone outside of the generic ARM cores - which makes sense - Broadcom, for a while, was an architecture licensee of ARM... Asus' GPL drops include the Broadcom toolchain and optimized kernel and compiler, and it's probably the best one at present without an NDA with Broadcom.

The BCM4908 is more than just the B53 cores - it's also the improvements in the switch fabric, memory controller, and it's built on a newer process, which enables better clocks speeds and lower temps. It also benefits from improvements in the SDK that is provided to the OEM's - newer kernel, libraries, toolchain...

It's a reasonably decent performer, and a good step up from the older Cortex-A9's* used in earlier Broadcom consumer router SoC's - the crypto performance is very good according to discussions with people "in the know"

* Broadcom's Cortex-A9's were nominal - e.g. no VFP, no NEON, as they were optional on Cortex-A9 - performed well enough for the time. Broadcom had a great run with that chipset in 802.11ac Wave 1 where they pretty much covered every OEM in the consumer space.

 

[Razor512]

Will the new SOC still support overclocking?

 

[sfx2000]

Will the new SOC still support overclocking?

Hard to tell - many Broadcom chips have a section of One Time Programmable Memory (OTP), where if a value is written there, it overrides configuration settings that might be sent - the chip's firmware will accept a written value, but once OTP is committed, it's basically ignored...

Good example - outside of the Router SoC's - the BCM2837 used in the Pi3 has a feature in silicon where one can enable Network booting, so the boot vector first looks at a network source before the SDCard to load the bootloader - once that bit is set, it's set forever, no matter what you do - you can attempt to flip that bit/setting, and the chip will say "ok", but it won't actually set that bit.

It's known that other BRCM chips also do this for various functions, and it's done by other vendors as well in the SoC space.