As far as I understand the rules for coding programs, you write a program of Rating X from scratch, i.e. if you write an Attack 4, it's threshold 8 with 1 month intervals. Once that is done, you have an Attack 4 program.

But what if you already have an Attack 3 program and want to upgrade it to 4?

How would you handle this?

I thought about just needing the difference between the old and new rating +1.

Or is this actually covered somewhere, and I simply missed it?

Bye
Thanee

That is not covered for SR4 (yet). There was a mechanic for upgrading programs in SR3, if I remember correctly. You could upgrade a program by spending the difference in time between the rating you have an the rating you wanted, similar to what you described above. Unless someone else has a copy of Matrix handy, I'll try to remember to look the info up and summarize it when I get home this evening.

IIRC, thats how it worked in SR3, if you had the sourcecode of the program.

In our group, we have "upgrading" rules for all kind of stuff, letting you pay only the difference between the old and the new levels. Attack 3 -> Attack 4 would be 1000 Nuyen(4000 Nuyen - 3000 Nuyen).

I'm wondering about upgrading the OS program.

What if say a character were to purchase a Vector XIM OS (Firewall 1, System 1) and wishes to upgrade it to (Firewall 6, System 6). Does the character:

a.) Write/Purchase a Firewall 6, System 6 OS (3K each or 6K total)
b.) Upgrade per rating between:

Rating 2 = 400
Rating 3 = 600
Rating 4 = 2000
Rating 5 = 2500
Rating 6 = 3000

for a total of 8500 each for the firewall and the system (total of 17K )

As far as I understand, the cost for a Rating 6 program is 6,000¥, so when you upgrade from a Rating 1 program, it cannot cost more than that.

Bye
Thanee

I didn't say that... as you can see above, there are no real rules for upgrading.

You could simply have it cost the difference, between what your current program did cost and what the new one would cost in total.

Bye
Thanee

You can buy the upgrades for the OS, just purchase the desired rating and whammo that's the cost. As mentioned there are no rules for upgrading software in the current state of the game.

Since rating 6 seems to be the cap for most things, where 7+ are eluded as being military or better apps, I'd wonder if they'd ever allow players to achieve it short of stealing it.

They could always try to write it themselves