![]() ![]() When the computer connects to the internet it uses a protocol called PPP. The problem we saw with the spoofing is that you only get around 60 seconds before your email program gets bored and disconnects anyway, which isn't very much time to fix the original problem and redial - hence it wasn't a terribly useful product and is now discontinued at Iridium The product doesn't appear to offer any additional compression over and above normal PPP compression. This means that if the real internet connection dropped, then the Apollo Emulator would pretend that it was still there and prevent your email application from showing an error message. Curiously, "Connected at 19,200" means your Iridium internet connection is actually slower.Īctually as far as we can tell the Apollo Emulator product was mainly useful for connection "spoofing". The implications of this are that there is no warble while each end handshakes and instead you are directly connected to the Iridium Direct Internet gateway in just 10 seconds!Ĭonclusion: "Connected at 9,600" is good. However, if you see the "Connected at 9,600" message then curiously this means that you are connected via a faster ISDN digital connection. Clearly it's less optimal to use a digital network to use analogue tones and whistles to transmit what started out as digital data in the first place! Essentially the Iridium is converting the signal into analogue squeeks and whistles, transmitting them over a digital network then the other end is converting these modem noises back to digital again (that's what a modem does!). The implications of this are that it normally takes around 20 seconds of chargeable airtime to connect to the Iridium ISP and the connection is usually not quite optimal and more vulnerable to interference and disconnects. If you see the "Connected at 19,200" message then this indicates that you are connecting like an old style analogue mode (ie it does that warble and spends some time synchronising speeds with the far end). The connection is then made instantly and all data is transfered digitally from end to end (no conversion to analogue).Ĭlearly this is the most optimal way to use a digital telephone connection! This is standard across all modern modems and basically switches the modem into an ISDN emulation mode running at (an emulated) 9,600 baud (called V.110). The faster speed of 9,600 is achieved by using the standard AT command sequence: ![]()
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