The availability of today's typical bandwidth connectivity and always
on connections to the home has several implications for security, both
computer security, and physical security.
Computer SecurityBefore the availability of our always-on internet connections, the effects of computer viruses and other pieces of malicious software was limited to the infected machine, and perhaps those receiving email from an infected machine. Because bandwidth was limited, the rate of spread of infections was limited. Today, where an infected machine has a high-speed connection to the network that is almost always on, the infected software can readily lie dorman until it is triggered by receipt of a message or by some other change in state elsewhere on the network. This gives rise to the problem of bot-nets, large collections of home machines controled by others, often with ties to organized crime. For this reason it is extremely important that you keep your systems up to date with the latest patches, and install antivirus and other security software on your system, as well as configure your firewalls to limit certain kinds of attacks.
Bandwidth encrourages downloadsAnother threat that is more prevalent in high bandwidth environments is that users are more likely to download software from web sites that they have not properly vetted, vs the old approach to using software that you purchased shrinkwrapped at a local retailer. If you download software from an untrusted site, there is high liklihood that the software may have been modified to do things other than the functions you through it was performing. Such software can steal data from your hard-drive, or install nodes on the bot-nets describedin the last section.
Security CamerasNot all is bad about high-bandwidth connection, however. There are now security camera systems that are readily available that allow remote monitoring over the internet. There have been several cases where users have observed their homes being robbed and contacted the police who were able to apprehend the burglers.
But, if you have web accessible security cameras, consider that like any computer system, there may be vulnerabilities that give access to others, either by exploting bugs, or by stealing the password you set up, or for that matter, in some cases by obeserving the network traffic eminating from your network. This can affect your privacy, and for this reason I suggest that if you make video streams available over the internet that you set up cameras only in public areas of your house - and preferably only on the exterior. If you need cameras for the interior, place them on a separate system without network access.