Been wondering for a while and can't find an answer. I have 2 android tablets with wifi and a verizon 4g jetpack wifi hotspot. If I use a program to transfer files between these tablets over wifi, does the wifi hotspot forward the data from tablet 1 to tablet 2 or does tablet 1 connect directly to tablet 2 and leave the hotspot out? During this time there is no activity on the 4g side. I like knowing how things work and this has been bugging me for a while. I'm assuming it goes through the hotspot but I'd like to know for sure. Ive searched google with no luck, most links are to 300+ page documents I don't have the time to go through.

 

Usually (not Ad-Hoc Mode) there is an Ethernet switch fabric in the router that sends subnet packets directly back and forth on the WiFI side to connected clients. Exactly how it works depends on the configuration like explained above.

I mainly use hardware that's compatible with https://en.wikipedia.org/wiki/DD-WRT

and use the Client Bridge configuration to my main hardwired Linux NAT firewall and router.

 

I think my setup is like the left with one access point (the hotspot) and 2 tablets connected to it. I'm guessing ad-hoc mode isnt something my tablets would be using, so that means my hotspot is involved in the transfers. Thanks

 

I think my setup is like the left with one access point (the hotspot) and 2 tablets connected to it. I'm guessing ad-hoc mode isnt something my tablets would be using, so that means my hotspot is involved in the transfers. Thanks

Yes....the configuration is not ad-hoc mode.

Basically, you are using your hotspot as a wireless WiFi bridge connecting the devices. So..yes...the traffic goes thru the hotspot to get to each connected device.

Ad-hoc mode is a peer-to-peer type connection where each device communicates directly with each other.

 

The 4g part may not see it as chargeable traffic though,because it isn't technically using the 4g network.

 

I hope you don't mid, if I hyjack this thread a bit, since Robert seems to know what's going on.

This is how I understand DSL Bridge mode: The DSLAM is about a mile away and communicates via ATM to a place about 50 miles away.

The ping to my public IP address from the Internet, essentially gets returned by the place 50 miles away. I don;t think it even reaches my network.

When I ping my public IP address from within my NAT'ed private network, I would get a response from the place 50 mies away.

The bridge essentially does nothing.

Usually, the ISP blocks the ping packet anyway.

 

Network bridges are rarely used anymore as their Layer 2 functions are incorporated into switches. Bridges were more commonly used when LANs were wired using hubs. Now that switches are ubiquitous, there is no need for bridges in most networks (wireless bring the one remaining networking application where bridging is used, but your diagram does not show this case).

 

The ISP likes to combine the router/AP and switch together, BUT fro some STUPID reason the switch ports are at 10/100 mb/s and the 802.11 portion supports wireless n (300 mb/s) or wireless ac, so it's just plain stupid. So, I don't use this method.

I have a RAID server, so I am severely limited if I use their method. My DSL speed is only 3mb/750k. It's also stupid because the older modems give line statistics and the new ones don't. With Verizon, their new modems always assumes your modem is new and it won't let you connect to an existing line unless you go to an alternate page. The modem password can be anything or nothing now. It's a physical line.

Way back when, I put the modem where it belonged - very close to the NID with a splitter in the NID and the wireless where it belonged - the center of the house. If you go back farther in time (like 1994), I had a power line Ethernet between the modem and the wireless router and free wireless b over PPP (Dial-up). The house is a weird mix of QUAD cable and non-home run with way too many telco devices, but yet the technician said my DSL line is "pristine". There was always one wireless repeater.

My UPS died and I haven't yet connected the new one. the one I bought was a little big, but has the server shutdown interface. I also ran the DSL modem on POE. Wiring from the modem to the center of the house is hard to do. That would leave a repeater with a non-backed up power source. The repeater provides better coverage outside and in one room.

There is always this hassle - you can't see the DSL modem interface when in Bridge mode,

http://superuser.com/questions/859490/how-do-i-access-my-modems-gui-when-its-in-bridged-mode

AND, I really have to reduce my network to modem and laptop when troubleshooting with my ISP or for me to see the commissioned speed.
re-configuring is a PITA. So, it would then be a little more parts, but basically OK.

So, to address some of these issues, I have to robustly mount my DSL modem and spare DSL modem on a DIN rail in the rafters in the basement.
The spare broke plastic keyhole screw mounts and I'll add a triple A/B switch (CAT 6 rated) that can switch the DSL and WAN ports of both modems. I can then plug-in locally and access a non-bridged modem directly at a more convenient wired location. The A/B switch will retain it's last position on power off. FWIW: It is RS232 controllable.

I have two ASUS RT-AC68U routers that I plan to run the Merlin firmware. Right now, they are acting as repeaters and one is acting as a local gigabit switch for troubleshooting an IPTV system/ATSC modulator unsuccessfully. I haven't been able to connect to it with VLC and I haven't been able to test the analog output with a TV. I do have presence of a valid signal (BER OK, signal strength OK) measured with a tester.

I suspect, I'm going to have to upgrade to a 24 port Level-3 switch to support Multicasting correctly. There is both a management port and a streaming port on the modulator.

I DID manage to stream a file from my laptop to an IPTV directly.

So, lots of plans, little understanding and no time.

 

Network bridges are rarely used anymore as their Layer 2 functions are incorporated into switches. Bridges were more commonly used when LANs were wired using hubs. Now that switches are ubiquitous, there is no need for bridges in most networks (wireless bring the one remaining networking application where bridging is used, but your diagram does not show this case).

Expanding a little on your comments....

Ethernet LAN Switches are basically multiport bridges. The original function of a bridge was to extend a layer 2 network segment, which inherently create an additional collision domain. Back in the day these bridges usually only supported two ports. But with the use of modern day switches that utilize a switching fabric to forward frames, they are no longer called "bridges" but are called layer 2 switches, with port capacities of 24, 48, or greater fairly common.

LAN hubs are layer 1 devices and were used to provide more ports for connecting network devices like workstations and printers. There was a finite number of hubs you could connect in a LAN segment before violating Ethernet segment standards. Too many hubs would prevent the reliable detection of collisions.

 

I think my setup is like the left with one access point (the hotspot) and 2 tablets connected to it. I'm guessing ad-hoc mode isnt something my tablets would be using, so that means my hotspot is involved in the transfers. Thanks

One simple test is to simply shut off the hotspot and see if you can still transfer anything between the two tablets.