Last week, Apple released Open Transport/PPP 1.0, its first in-house implementation of PPP, the protocol most people use to connect to the Internet via a modem. Although many varieties of PPP are available for the Macintosh - including versions of MacPPP, FreePPP, and NTS PPP, plus other commercial options - OT/PPP is the first version to be Open Transport-native (rather than relying on mechanisms designed for MacTCP) and only the second PPP implementation to be supported officially by Apple.
However, don't make the assumption you need to turn your Internet world upside down and bring OT/PPP into your life. Though OT/PPP may benefit a number of dialup Internet users, the Golden Rule of PPP applies: if you're happy your current PPP software, there's no strong reason to change it.
Where and How -- OT/PPP 1.0 is available from Apple's sites as a disk image or as a Net Install package including an Acrobat PDF version of the manual. (The manual can also be downloaded separately.) Either way, the full package is about 2 MB.
OT/PPP requires a 68030 processor or better and Open Transport 1.1.1 (also available from the URL above; see TidBITS-351). Apple recommends using OT/PPP with System 7.5.3 or higher, although it can also be used with System 7.1.x. Even so, OT/PPP cannot be used with System 7.5, 7.5.1, or 7.5.2 - you can upgrade those versions to System 7.5.3 or 7.5.5 for free.
It's always a good idea to back up your Mac (or at least the System Folder) before installing new system software. However, you don't have to remove PPP software: OT/PPP co-exists with it just fine (see below).
Using OT/PPP -- You configure OT/PPP in the new Modem and PPP control panels, and online help is available via Balloon Help and Apple Guide. Like Open Transport's AppleTalk and TCP/IP control panels, the Modem and PPP control panels can switch between saved configurations without restarting the Mac. The PPP control panel tracks your dialup username and password (if any), along with your provider's phone number and a set of dialing and other options. The PPP control panel also features send and receive indicators (so you can tell what your modem's doing) and a built-in logging feature. Though the log's verbose mode can be useful for troubleshooting, it might not capture all the information your provider needs to diagnose connection problems.
The Modem control panel lets you select your modem type and options. Unlike MacPPP or FreePPP, however, OT/PPP uses modem scripts (called CCLs) to manage modems. This is a mixed blessing: on one hand, CCLs allow more sophisticated control than modem init strings, and CCL scripts are also used by Apple Remote Access. On the other hand, writing CCL scripts is more art than science: if OT/PPP doesn't come with a functional script for your modem, you might be out of luck. [Worse yet, my experience with the first edition of Internet Starter Kit for Macintosh and InterCon's free InterSLIP indicates that normal users detest working with CCL scripts. -Adam] Apple, Info-Mac, and other sources maintain archives of third-party CCL scripts, and Apple has an unsupported Modem Script Generator in the OT/PPP Extras package - it can help create CCL scripts, and contains some CCL documentation.
Once everything is configured, making a PPP connection with OT/PPP should be as simple as clicking the Connect button in the PPP control panel. If you previously used Open Transport, you'll probably have to open the TCP/IP control panel and change your settings to PPP instead of MacPPP or FreePPP. Save the current TCP/IP setup (using the Configuration dialog) before switching to OT/PPP; that way, reverting will be easier if something doesn't work.
Performance & Memory -- Reports vary, but testing on my Power Mac 7600 shows OT/PPP is slightly faster than FreePPP 2.5 on my Supra 28.8 modem (usually between 50 to 100 bps faster during sustained transfers). This improvement might seem tiny, but remember the bottleneck is the sluggish pace of a modem. Users of ISDN terminal adapters and other higher speed PPP connections can expect bigger improvements. Also, because OT/PPP is Open Transport-native, the performance of applications developed specifically for Open Transport will improve.
However, OT/PPP's performance comes at a price: an additional 500-600K of RAM, plus a little over 350K for the PPP control panel (if you leave it open). Considering that Open Transport itself requires 500-1500K of RAM, that's a lot of overhead, especially for Power Macs currently using MacTCP.
Other Features -- Unlike other PPP implementations, OT/PPP is scriptable right out of the box, so scripters can automate PPP connections using AppleScript, Frontier, or other tools. Though OT/PPP's scriptability is nice (and the sample AppleScripts are straightforward), it's not a compelling reason to switch, since Mark Aldritt's Control PPP scripting addition gives some script control to MacPPP and FreePPP users.
Fortunately, Open Transport's flexibility lets OT/PPP co-exist with previous installations of MacPPP, FreePPP, and other PPP implementations quite happily. If you use Open Transport, just create different configurations in the TCP/IP control panel, then use the Configurations dialog to switch between them.
For frequent travellers, OT/PPP might be a step backwards from FreePPP. Although the Modem, PPP, and TCP/IP control panel all store configurations, managing those multiple setups is difficult compared to FreePPP's location settings. Some people strongly prefer FreePPP's interface, although I don't feel passionate either way.
Do You Need OT/PPP? OT/PPP is well-engineered (having undergone thorough internal and public testing), and reports so far indicate that OT/PPP can be more stable than FreePPP or MacPPP. If your current PPP setup has been problematic (and you have the RAM), OT/PPP is worth investigating, particularly if you already use Open Transport 1.1.1. Similarly, if you need some of OT/PPP's features - strong Open Transport compatibility, improved performance, configurations, or scriptability - then OT/PPP is probably for you.
However, Apple will continue to support its release of MacPPP for some time, and the FreePPP Group is continuing to develop and refine FreePPP. Once again, remember the Golden Rule of PPP: if you're happy with your current PPP software, there's no strong reason to change it.