ISP PlusNet Launch Faster Hub Zero 2704n Broadband Router

Veri · ‎09-03-2015

Not sure if this warrants a new thread or this thread's a clearinghouse for potentially missing features... I can't see any way even on expert_user.html to get the 2704n router responding to ICMP pings on the WAN side.
Certain things e.g. HE 6in4 tunnelbroker want to check the host is up with a single ping on changing IP address, and I've found it works to temporarily set a DMZ host which responds to it, but this doesn't help e.g. for continuous quality monitoring which sends regular pings.
Do I have to set a permanent DMZ host (which seems overkill), or am I missing an obvious setting somewhere please?

Oldjim · ‎15-06-2007

responding to pings is blocked permanently due to "security concerns"

nanotm · ‎11-02-2013

which is odd given that iptv requires igmp responses, or do they allow type3 igmp ?
either way igmp response blocking is the easiest way to defeat ping of death type DDOS attacks which can crash an entire isp service in seconds.....

just because your paranoid doesn't mean they aren't out to get you

Darsh · ‎12-03-2015

nanotm, you are confusing ICMP with IGMP. ICMP is pings, IGMP is multicast.

Darsh

nanotm · ‎11-02-2013

oops yeah, I was just reading something the other week about type 3 ping requests and totally forgot about ICMP, although you can still do the same thing with igmp as icmp (initiate P.O.D. according to the article I was reading).
I think until we move over to ipv6 were going to be stuck with more and more non operational parts of the old ipv4 standards ....

just because your paranoid doesn't mean they aren't out to get you

Anotherone · ‎31-08-2007

Quote from: Veri
Do I have to set a permanent DMZ host (which seems overkill), or am I missing an obvious setting somewhere please?

I suspect that may be the only solution, as Jim pointed out, responding to ICMP pings was not a setting provided on the 2704n

Veri · ‎09-03-2015

Quote from: Oldjim
"security concerns"

AIUI an echo reply won't be larger than the request so can't be used in an amplification attack (assuming broadcast packets are dropped!), and any sensible host would rate-limit replies anyway. I can see the potential for a ping with spoofed source = intended destination and payload = data used to bounce data to a third party, but this is hardly the cleverest way of achieving anonymity. I hope it's not the old, "It shows there's someone there."

indeed!

Veri · ‎09-03-2015

ISSUE
It seems devices listed as "Unknown-xx:xx:xx:xx:xx:xx", i.e. ones for which it isn't picking up the device name, are mixed up when it comes to port forwarding. IOW
1) I had two devices listed as Unknown-aa:aa:aa:aa:9d:76 and Unknown-bb:bb:bb:bb:e5:25;
2) I set up a port forward to Unknown-aa:aa:aa:aa:9d:76, a Windows workstation which didn't have its name picked up;
3) Eventually packets end up being forwarded to bb:bb:bb:bb:e5:25, with the UI confirming this (enc.).
The DHCP server on my network assigns a static IP address to aa:aa:aa:aa:9d:76, so it's not that it's following IP address assignment either :/.
FIX FOR THIS CASE (i.e. how to get it picking up the device name)
My fix comes from realising that the workstation came up as Unknown because the router sent an NBT query to port 137 for the device's NetBIOS name (table) just after it receives an ARP response from the workstation during boot-up, i.e. either before the relevant Windows service has started or while the anti-virus is still starting up and blocking port 137, so no response is received.
So, if I 1) release the workstation IP; 2) wait long enough and/or reload the router home page (which sends everything an ARP request to refresh the list of connected devices, afaict flushing the ARP entry); 3) renew the workstation IP; then 4) refresh the router home page again, it picks up the device name properly.
Hope that's not too babbly, but I learned some things so it might be useful!

VileReynard · ‎01-09-2007

Do individual devices retain rubbish in their ARP caches though?

"In The Beginning Was The Word, And The Word Was Aardvark."

Anotherone · ‎31-08-2007

Jeremy, do you think you could explain your comment in more detail. To my simple way of thinking, and not being an expert on this particular issue, if any Cache has never had a relevant entry or if the device has only just booted then the cache will not contain anything or contain rubbish?
@Veri, sounds very useful, thanks

VileReynard · ‎01-09-2007

Each machine keeps a cache of ARP addresses:-
See http://www.petri.com/csc_arp_cache.htm

"In The Beginning Was The Word, And The Word Was Aardvark."

Veri · ‎09-03-2015

ARP in essence merely involves a broadcast asking who-has a particular IP address and the local machine with that IP address responding with its MAC address, and afaict all machines here are giving appropriate responses, so no rubbish has an opportunity to enter any ARP cache. Devices getting "Unknown-" names on the 2704n seems to stem from the router not making much effort to ask again for a NetBIOS name (not an ARP thing) if it fails the first time, and entry for device "Unknown-aa:aa:aa:aa:aa:aa" ending up producing a forwarding to e.g. bb:bb:bb:bb:bb:bb may be because the router doesn't actually associate that name with either the MAC address or the IP address at the time, but decides it can treat "Unknown-" devices interchangeably? I'm not sure.

30FTTC06 · ‎18-02-2013

I keep getting an interesting entry in my arp table.
192.168.0.21 Incomplete 00:00:00:00:00:00 br0

crazydan7 · ‎25-11-2013

hi,
ok so can people confirm weather this is just me having this issue, or weather it's something to do with the firmwhere?
i got the new router yesterday and set a new router password through expert_user.html
i then changed the default password to one of my own, confirmed it twice as you do, and now i am unable to log in to the router with the new credentials both through the standard plusnet 192.168.1.254 or 192.168.1.254/expert_user.html
does anyone know why this is?
i even tried the old login just encase for some reason the router auto reset it back but still no joy?

VileReynard · ‎01-09-2007

Since 192.168.0.xxx is a different network to 192.168.1.254 it's hardly surprising...