Man-Kzin Wars IX, Larry Niven [leveled readers TXT] 📗

Our destination was a cargo box, but this one had doors and large windows cut in the sides. Powerful lights were mounted flush with the walls. Jocelyn thumbed a door open and waved us in. "We use this for troubleshooting and inspections. It carries everything we need, and we don't have to shut down a tunnel to use it."

Inside the container was mostly empty space. There were doors and windows in the floor and ceiling as well as the walls and all the surfaces were padded and well equipped with handholds. Strapdown chairs with mounts that locked into the handholds were set up beside the forward windows. A quarter of the bottom rear was given over to a series of cabinets that housed batteries, switches and various tool chests. Beneath the forward window there was a spartan control board with a compact data terminal as well as various buttons, gauges and comm gear. Beside it was a small keypad. I recognized it at once from the tranship operations manual. It was the container's shipping control panel, a duplicate of the one mounted on the outside.

I walked over and examined the panel. When Jocelyn joined me, I asked, "This contains the tranship codes?"

"Not just the codes, everything about the shipment. The freight manifest, maximum and minimum allowable temperatures, power requirements, loading parameters, whether the container is pressure sealed, center of mass, priority level, customs codes, COD status and charges. Everything." She tapped a few keys and cryptic data slid over the small screen inset on the panel. PRI, COD, KPA, BOT, and others along with numbers that didn't mean anything to me. I did recognize two codes. SRC and DST indicated the container's source and destination—both were rack addresses in the up-axis hub.

I tapped a few keys and managed to bring up the DST code. "Can you set this up to go anywhere?" I asked Merral.

"Anywhere on Tiamat. The lockouts don't allow us to be loaded for an offworld destination. This container isn't vacc sealed. I'll set it for the outbound receiving racks at the down-axis hub with a routing override so we get tunnel nineteen. That'll take us right through Tiamat."

It was better than I'd hoped for. "Can you try TMU19J234C?" I asked.

She looked at me with the half accusing "How do you know what that means?" look that's usually reserved for medical patients who show their doctor some basic piece of medical knowledge. Specialists hate it when you trespass on their specialty. It makes them less special. Nevertheless, she thumbed the pad to authorize the change and punched in the destination code. After a couple of seconds the screen displayed accepted, then reverted to DST: TMU19J234C.

"This transaction is now logged in the transport net, correct?" I asked.

Merral nodded, adjusting the restraining straps that held her in her seat. She motioned for me to do the same.

"Is there any way to circumvent that?" I asked, fumbling with the belts.

"How do you mean?"

"Can you enter destinations into this panel without having the system become aware of it."

"It could be done. You'd have to block the scan transceiver and trick the panel into thinking it had transmitted the change and received a valid authorization verification. It wouldn't be easy, we use dynamic encryption. Why would you want to?" She reached over and helped me get buckled in.

"A smuggler might change an onworld destination for an offworld destination, or perhaps just make a shipment the system isn't aware of."

"I see what you're getting at, but you misunderstand me. If you prevent the panel from talking to the net, the net will just ignore it. It won't get sent anywhere. There's a lot of ways to break the system, but once it's broken it won't work properly."

"I don't follow."

"Look, the system is vulnerable to tampering and there's no way to avoid that. Rather than try to make it tamper-proof we've made it fail-safe. Getting a container to move involves a series of steps, with our control procedures built into the chain. If any link is broken the system flashes us a trouble warning and won't move the container."

"And the data in the panel itself is all self-encrypted so you need a Port Authority ident to change it, correct?"

Merral warmed to her topic. She obviously enjoyed having someone show an interest in her work. It probably didn't happen too often. "Not quite. The source address is always locked so we can back-trace a shipment, nobody can change that. When the shipment arrives and is accepted, the destination address is copied to the source so the container can be sent out again. Manifest, COD charges and destination are set by the shipper and then locked when the PA verifies and seals the shipment. The user functions—like humidity, temperature and all that—can either be set and locked or left open at the shipper's discretion in case they need adjustment in transit."

"So you can't change the source or the destination in transit unless you have a Port Authority ident."

"Not even if you do have a PA ident. Once a setting is locked, it can't be changed until the receiver accepts the shipment and signs off with us. The system only lets that happen at the destination address."

"What if you hacked it, opened the box and modified the software?"

"All you'd do is cause a self-encryption verification failure. The system would halt the container at the next control point and drop a trouble flag."

"What if I supplied my own panel that allowed in-transit re-routing?"

"It still wouldn't work. Firstly, it would fail PA verification at the point of shipping. Second, the tranship net and the panel would disagree on the destination as soon as you modified it. The net would halt the container and you'd get another flag. It's fail-safe."

Fail-safe. It's a one-word lie. Nothing built by humans is fail-safe. I knew someone was playing games with the tranship net. What Merral was really telling me was that I needed to look for hackers in the net's high-level control software