Comment by tptacek

13 hours ago

Your own sources confirm what I'm saying.

> Your own sources confirm what I'm saying.

I don't see where they do. I see them talking almost exclusively about working around address depletion.

Hell, look at Cisco's press release for its acquisition of Network Translation, Inc. [0] It's all about address depletion and resource efficiency; security is mentioned as an afterthought. I'll quote the relevant paragraphs (and leave in the line break mangling present in the original).

  SAN JOSE, Calif., October 27, 1995 - Cisco Systems Inc. today announced anagreement to purchase privately-held Network Translation, Inc. (NTI), anetworking manufacturer of cost-effective, low maintenance network addresstranslation (NAT) and Internet firewall equipment. The investment isintended to broaden Cisco's offerings for security conscious networkadministrators who want to dynamically map between reusable private networkaddresses and globally unique, registered Internet addresses. Through itsacquisition, Cisco will gain NTI's Private Internet Exchange (PIX) solutionwhich helps network administrators resolve their growing need forregistered IP address space. NTI's 10 employees and products will beincorporated into Cisco's Business Development efforts reporting to VicePresident Ed Kozel. The financial terms of the purchase are not beingdisclosed. The transaction is expected to close by the end of November andis not subject to the Hart-Scott-Rodino filing.
  
  The NTI investment is the second action by Cisco in recent months tostrengthen its expertise in resource-effective Internet access technology.NTI technology will interoperate with and integrate several functions ofthe Cisco Internetwork OperatingSystem(tm) (Cisco IOS) software,facilitating use throughout the enterprise. NTI addresses two of the morecompelling problems facing the IP Internet -- IP address depletion andInternet security. Customers using the NATalgorithm can take advantage ofa larger than assigned pool of addresses. NAT makes it possible to useeither your existing IP addresses or the addresses set aside in InternetAssigned Number Authority's (IANA) reserve pool (RFC 1597). Cisco's goal ofintegrating NTI's technology and personnel is to ease the complexity ofInternet access for applications including telecommuting and World Wide Webaccess.

[0] <https://newsroom.cisco.com/c/r/newsroom/en/us/a/y1995/m10/ci...>

  • Read the Data Communications article they provided:

    PIX also increases network security. Since there's no way for anyone on the Internet to know which machine on the corporate network is using a Class C address at any given time, it's impossible to establish a telnet or FTP session with any particular device.

    And what about hosts that should be recognizable from the Internet, such as mail servers? These either can be directly attached to the Internet and assigned a public address or can be attached through PIX. In the latter case, the translator is config- ured to map one of the external addresses to the device not just for the duration of an application session but on a permanent basis.

    At some point you're going to have to find a way to argue that the Cisco PIX was not a security device; again: it was the flagship product of the security SBU.

    I was there at the time, doing IP network engineering (for a Chicagoland ISP). The PIX was a security device, and NAT was understood as a security feature (for sure, also an address depletion feature, but the argument that's being made in the post isn't merely that it was an address depletion thing, but also that it categorically wasn't a security feature, which is just obviously false.)

    • > At some point you're going to have to find a way to argue that the Cisco PIX was not a security device...

      What? It's a firewall that can do NAT. The PIX is clearly a security device. NAT is clearly an address-depletion-mitigation technique.

      > Since there's no way for anyone on the Internet to know which machine on the corporate network is using a Class C address at any given time, it's impossible to establish a telnet or FTP session with any particular device.

      Right. And you can achieve the exact same effect with a firewall on an edge router or on a host. I get that firewalls might have been much less common thirty-ish years ago and that doing packet filtering might have been pretty novel for many, leading folks to get confused when they encountered a combination firewall+NAT device.

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