Blinking light
 

Quick question. I have a superhub 1. After coming back from our holiday the blue light is constantly flashing. I'm pretty sure it wasn't before we went away. Is this normal?

Re: Blinking light
 

It is normal to be flashing, especially if you have a TBB gragh setup, nothing to worry about.

Re: Blinking light
 

Cheers

Re: Blinking light
 

You may well have been moved to a new piece of kit on Virgin's network that works slightly differently.

Re: Blinking light
 

The bit I don't understand, Igni, is that this is CPE behaviour. Is the flashing light a command bit or something like that in all data?

Re: Blinking light
 

I was told by an engineer checking my power levels sometime after my SH1 was installed that the constant flickering occurs when more than four downstream channels are in use. This agrees with my experience and that reported by others.

Re: Blinking light
 

Cupcakes (the OP) might care to tell us if there were only 4 DS channels previously in use.

Re: Blinking light
 

If by four downstream channels you mean four devices in use at once then no the flickering occurs as soon as the modern boots up.

---------- Post added at 17:49 ---------- Previous post was at 17:48 ----------

We do have four devices using the modern at times but the flickering does not coincide with this

Re: Blinking light
 

Downstream channels are your hub's connections to the internets, via the Virgin Media network. The superhub uses multiple channels, in order to deliver superfast internets to your home.

Re: Blinking light
 

Most people should now be on 8 downstream channels (QAM256) and 2 upstreams, ideally on QAM64.

Re: Blinking light
 

I've yet to see QAM64 in my area.

Re: Blinking light
 

The Arris CMTS are edge routers with CMTS cards attached. What the customers are seeing are ARP broadcasts.

With the 'dedicated' kit there are no ARP broadcasts; the CMTS takes care of them by remembering what MAC addresses are where and querying the DHCP server as required if it needs information, then dropping any ARP broadcasts that are sent and responding to the querying device via a unicast.

I have no idea if there's functionality within the Arris equipment to do this, but for right now if there is it's not active, so I presume it's required for the E6k to do its thing.

---------- Post added at 23:06 ---------- Previous post was at 22:55 ----------

The engineer was mistaken.

Re: Blinking light
 

One upstream's been QAM64 for ages, the other was shunting between 16 and 32 but now seems to have settled for 64.

US-1 US-2 US-3 US-4
Channel Type 2.0 2.0 N/A N/A
Channel ID 68 66 N/A N/A
Frequency (Hz) 53700000 Hz 35800000 Hz N/A N/A
Ranging Status Success Success N/A N/A
Modulation QAM64 QAM64 N/A N/A
Symbol Rate (Sym/sec) 5120000 5120000 N/A N/A
Mini-Slot Size 128 128 N/A N/A
Power Level (dBmV) 50.0 dBmV 50.0 dBmV N/A N/A
T1 Timeouts 0 0 N/A N/A
T2 Timeouts 0 0 N/A N/A
T3 Timeouts 3 3 N/A N/A
T4 Timeouts 0 0 N/A N/A

Upstream power is possibly a little close to the edge but the service seems reliable enough. Downstream is almost perfect figures.

Re: Blinking light
 

Wait, does this mean the Arris kit is open to arp spoofing?

Re: Blinking light
 

SHHHhhhh!

Re: Blinking light
 

Nah. ARP inspection / DHCP snooping.

Re: Blinking light
 

And that's impossible.

Re: Blinking light
 

What's impossible?

ARP poisoning is perfectly possible if mitigating steps aren't taken. ARP inspection and DHCP snooping are standard mitigation methods, as is ARP filtering.

Re: Blinking light
 

I was being sarcastic Igni.:D:D:D