Chapter 286: Protocols and Bridging

At two o'clock on Sunday morning, the curtains in the rented room were drawn tight. Lin Chen spread the old laptop from his canvas bag across the folding table, the cold light from the screen catching the dark hollows under his eyes. His left foot rested on a piece of stiff cardboard, an elastic bandage wrapped around the ankle. Numbness had already climbed up along his calf, like a layer of soaked, heavy cotton packed around his nerves. He unscrewed a bottle of safflower oil, poured some into his palm, rubbed it warm, and pressed hard on Zusanli and Chengshan. The sharp pain made him briefly alert again. He sat back down at the computer and opened the terminal.

The HIS system at City First Hospital was built on architecture from ten years ago. Its database schema was closed, and the only thing it exposed was a set of read-only views. The feature tags produced by the offline model had to be converted into a format the hospital could recognize before they could be embedded in the doctors' workflow. The "wireless real-time upload" Zhao Qiming had mentioned was the kind of story capital liked, but what clinical practice needed was stability. Lin Chen had no intention of touching a real-time stream. He wrote a lightweight bridging script, using a local cache as the relay: it read the CSV intermediary tables exported from the HIS system through scheduled polling, matched patient IDs and timestamps, then wrote the cleaned confidence labels back into a designated directory. No API. No cloud synchronization. Only the clumsiest kind of file exchange. He added three layers of validation to the code: timestamp alignment, non-empty field checks, and outlier truncation. If it could not run, it skipped the record and did not block the main process. A clinical site did not need perfection. It needed not to crash.

The door was pushed open gently. Su Man came in carrying a plastic bag with two warm portions of rice noodle rolls and two cartons of milk inside. She set the food on the corner of the table without interrupting him, pulled over a chair, sat down, and opened a printed stack titled On-Site Data Confidentiality and Responsibility Allocation Agreement. "I revised Wednesday's clauses three times," she said softly. "I bolded 'model output is for reference only,' and capped liability at the fee for a single service. If Director Zhou doesn't accept it, we don't sign." Lin Chen typed the final line of code, saved it, and ran the test script. The terminal printed: [BRIDGE] Local cache synced. 3 records mapped. He turned his head. "Clinical work isn't the internet. The tolerance for error is zero. What they want is not speed. What they want is for nothing to go wrong. Send the agreement in your version."

Su Man nodded and slid the agreement into a folder. She glanced at Lin Chen's foot and said nothing, only sticking a heat patch to the outside of his knee. Lin Chen did not refuse. He switched back to the code interface and began a stress test. With two thousand simulated concurrent data writes, the script's memory usage stayed steady, but the CPU on the old laptop spiked to 85 percent. The fan gave off a dull drone. He lowered the window refresh rate and stretched the polling interval from five seconds to fifteen. Good enough was enough. He did not need to show off. He only needed data to flow like water in an environment where power and network connections might both fail: no overflow, no blockage.

At four in the morning, the test finished. Every log line was green. Lin Chen closed the laptop and leaned back in the chair, eyes shut. The city outside the window had not yet woken; only the occasional sweep of headlights passed along the distant elevated road. He thought of Xiaoman convulsing with fever as a child, of the smell of disinfectant in the county hospital corridor, of his father squatting on the threshold and smoking a rolled cigarette. Those images were not sentimental. They simply pressed heavily against his chest. He opened his eyes, packaged the script, burned it onto a USB drive, and backed it up again to an external hard drive. Su Man had fallen asleep with her head on the desk, her breathing even. Lin Chen gently draped his coat over her, then went to the bathroom and washed his face with cold water. The person in the mirror had sunken eyes, but his gaze was steady.

At six-thirty in the morning, Lin Chen woke before the alarm rang. He slowly eased his left foot into a loose running shoe, tightened the laces, and tested his balance. The pain was still there, but he could walk. He woke Su Man, and the two of them packed up the equipment into two canvas bags. When they went out, the sky had only just begun to brighten, and there was an early-autumn chill in the air. They did not hail a cab. They walked along the sidewalk toward the bus stop. Lin Chen walked very slowly, deliberately letting his right foot take the weight first with each step, his left foot touching down lightly. Su Man carried the bag beside him, matching her pace to his. Neither of them spoke. There was only the soft scrape of soles against the ground.

At seven-twenty, they arrived at the administrative building of City First Hospital. The smell of peracetic acid in the corridor was stronger than the day before. The door to Room 304 was ajar. Lin Chen pushed it open and found that two more people were already at the long table, a man and a woman in dark-blue suits with "Zhinao Technology" badges hanging on their chests. The man was adjusting a portable EEG acquisition device; on its screen, waveforms and a three-dimensional rendering jumped in real time. The woman looked up at Lin Chen, her gaze resting for one second on his canvas bag, but she did not greet him. Director Zhou had not arrived yet. Technician Wu sat in the corner, looking down at his phone.

Lin Chen set down the equipment and plugged in the portable power supply. The voltmeter showed 11.8V. He opened the terminal and prepared to load the bridging script. A red warning box suddenly popped up on the screen: [ERROR] Network interface eth0 blocked by firewall rule. Local port 8080 denied. He frowned. The local loopback had worked in testing last night; why was even the intranet port blocked today? He checked the routing table and discovered that the hospital's information department had updated its security policy in the early hours. Local services on all non-whitelisted devices were now forcibly intercepted. Without the network, the bridging script could not read the HIS export directory. His fingers hovered above the keyboard as he quickly typed sudo iptables -L, and the output confirmed his suspicion. Su Man leaned closer and lowered her voice. "Information changed the rules at the last minute?" Lin Chen did not answer. He stared at the screen, his mind racing. Bypassing the firewall required administrator privileges, but the approval process would take at least two days. The demonstration began at nine. There were less than forty minutes left. He took out his phone, found Zhao Qiming's number, then put it down again. He could not wait. He switched out of the terminal and opened the system's low-level configuration, preparing to manually modify the local hosts file and routing table, using static mapping to trick the port interception. The risk was triggering a security audit, but it was the only path left. He pressed Enter. The screen flickered. From the far end of the corridor came the sound of leather shoes stepping on carpet. Director Zhou had arrived with the evaluation team.