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Network protocol nerd. Especially 802.11, TCP/IP, and Apple technologies.


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I hate downvoting, but I hate wrong or misleading information in Answers even more. I also don't like to "put words in people's mouths" by editing their Answers for correctness. So if I see an Answer with wrong or misleading information in it, I tend to downvote it and leave a comment explaining why, unless the Answer was so far off the mark or so riddled with errors that I didn't even know where to begin. If you edit your Answer to fix the problem(s), please let me know with an @Spiff comment! I will review the change, and if I agree that the errors have been resolved, I'll happily remove my downvote, and delete my critical comment. (Anyone can change their vote if the thing they voted on was edited after they voted.)


1d
revised MAC filtering not working on 2wire 2701HG-T modem
WPA2-PSK is the correct term, and it implies AES-CCMP. Also, the WPS vuln was overstated. Otherwise a solid Answer.
2d
answered Configure Raspberry PI Access Point to use RADIUS Apache Authentication?
Jul
28
comment DHCP letting multiple devices get same IP address - how to trouble shoot?
That sounds like a failure of both the DHCP server and the DHCP client. The DHCP spec recommends that servers ping the IP address they are about to OFFER, to make sure no one is squatting on it. It similarly recommends that DHCP clients send ARP requests for the IP address they have just been OFFERed, to make sure no one is squatting on it before they REQUEST it. Put a sniffer where it can capture these DHCP transactions, and make sure the AeroHive APs aren't all using the same DHCP Client ID (could be any admin-set string, or their MAC address).
Jul
28
comment Slow Internet speed when HomePlug combined with router
Your router won't serve DHCP out the WAN port. You have to give your WAN-connected machine a static IP on the same subnet as the static IP you gave your router, and set its default gateway to the static IP you gave the WAN port of the router.
Jul
27
comment Mavericks “ruined” my mac mini
What do your logs say?
Jul
27
revised Trying to figure out NAT between modem and router
deleted 20 characters in body; edited title
Jul
26
comment Not getting gigabit Ethernet speeds between 2 computers
Louie, what TCP window size did iperf report? Just for giggles, force it huge by adding -w 2M to both iperf command lines. What chipsets do your gigabit Ethernet interfaces (NICs) use? I'm leaning toward an answer of "you just have crappy NICs".
Jul
26
comment Not getting gigabit Ethernet speeds between 2 computers
@ChrisInEdmonton Even with standard 1500 Byte frames, TCP/IPv4 over gigabit Ethernet is 94% efficient (940+ Mbps). Jumbo 9000 Byte frames just let you squeeze another 4-5% out of the link.
Jul
26
comment Slow Internet speed when HomePlug combined with router
What speed do you get from the Upstairs PC, through upstairs switch, both HomePlugs, through the wireless router's LAN-side switch, to a machine plugged into a LAN port on the wireless router? Now take the downstairs machine and plug it into the WAN port of the wireless router instead of the modem (e.g. use static IP addresses to set up a point-to-point Ethernet WAN link; be sure to leave NAT on, but turn PPPoE off); what speed do you get from that WAN-connected machine all the way to the upstairs PC?
Jul
23
answered tar -czvf with no output file
Jul
22
awarded  Nice Answer
Jul
22
comment TCP traffic normalization
I don't think you defined what you mean by normalize.
Jul
22
answered How can I tell if Wireshark has sucessfully decrypted a capture
Jul
21
comment Will wireless clients connect to access points with the same SSID regardless of the wired network?
@BrianWheeler You can do it intentionally, but you'll be intentionally breaking clients' TCP connections and UDP flows whenever they roam. IPv4 Mobility never really caught on. Neither did SCTP or MPTCP. Many enterprise-class AP vendors have Wi-Fi mobility tricks where they watch for a client roaming from one building to another, and they tunnel that client's traffic back to its previous subnet so it doesn't lose connectivity. This can confuse users for why they're on the same SSID but different subnet than their colleagues in the same meeting room.
Jul
21
answered Will wireless clients connect to access points with the same SSID regardless of the wired network?
Jul
17
comment Port forwarding to second router's FTP server (linked via WDS)
Do you have any firewall rules set on the Netgear?
Jul
17
comment Port forwarding to second router's FTP server (linked via WDS)
Hmm, never mind I guess, that doesn't explain why other ports can't be forwarded to port 21 on your Netgear.
Jul
17
comment Port forwarding to second router's FTP server (linked via WDS)
Your TP-Link Archer D7 also has FTP server functionality. Did you get it out of the way by making sure it was disabled, and that its control port was set to something other than 21? I would do both just in case the firmware is buggy and reserves the control port even when the FTP server is disabled.
Jul
17
comment cannot capture packets on wireshark without internet
This is a long shot, but if you have Wireshark set to do name resolution, turn it off (in capture options). Maybe Wireshark is choking because it can't resolve any names when you don't have a connection to any DNS servers.
Jul
17
comment Don't have access to download files on Apache 2
What is the owner/group and permissions on the .7z file on the server? Is it readable by the account that Apache runs as?