With a cable modem or gateway, the ISP is in total control of the firmware; the customer has no options.
In my opinion a standard modem combined with a good quality standalone router is always a better choice than a modem/router gateway box (assuming that your ISP will allow you to do that). In this scenario, if you are renting the SBG6580 from your ISP, see if they will either replace it with a standard cable modem, or put it into bridge mode. If you own the SBG6580, you may be able to put it into bridge mode yourself, but some ISPs lock that function even for customer owned equipment, and will require you to call and have them put it into bridge mode (and some ISPs simply will not allow it). Here is a link to another thread in this forum describing how to put an SBG6580 into bridge mode: »Re: Another SGB6580 thread - helpuse as modem w/ own router
but I suspect that being able to do that will be very ISP dependent.--
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