Encryption Transaction with 3DES Team W2 Yervant Dermenjian (W21) Taewan Kim (W22) Evan Mengstab(W23) Xiaochun Zhu(W24) Objective: To implement a secure credit card transaction using 3DES encryption using Kerberos-style authentication. Current Stage: Full Chip SPICE Simulation 03/31/2004 Design Manager: Rebecca Miller

Current Status  Design Proposal (100% done)  Architecture Proposal (100% done)  Size Estimate and Floor Plan (100% done)  Full-chip Transistor-level Schematic (100% done)  Component Layout & Simulation (100% done)  Top-Level Layout (100% done)  Spice simulation of the entire chip (Successful) Need to find maximum frequency Need to find maximum frequency

Simulation Strategy  Simulate Entire Chip  Use same inputs from C and Verilog verification Encryption ensures multiple vectors over critical path Encryption ensures multiple vectors over critical path Each iteration tests different pattern over critical path Each iteration tests different pattern over critical path  Each time an iteration is run, SBOX determines new values that will initiate critical path  Run simulation for 20 clock cycles Will not produce final output but… Will not produce final output but… Values at each node should match Verilog Values at each node should match Verilog

Critical Path D8D8DBBC D8D8DBBCE73AED4F 80FF828E80FFC887 80FB848480FFC68C 80FFC68C Mux -> Expand -> XOR -> SBOX -> XOR -> Mux

Spice Simulation 100 MHz simulation

Close Ups 340ps 214ps

Problems Simulating  No DC path to ground errors Loose wires Loose wires  Quota exceeded errors Clear /tmp Clear /tmp Increase quota Increase quota  Simulation file inputs do not increase piecewise linearly Error in Java sim file generator Error in Java sim file generator  Degredation of Vdd! away from pin Modules near vdd! pin work correctly Modules near vdd! pin work correctly Modules further away have a lower vdd! Do not pass full 1.8 volts when PMOS passes vdd signal Modules further away have a lower vdd! Do not pass full 1.8 volts when PMOS passes vdd signal

Vdd! Problems  Simulation of Program Control and ROM using vdd! and gnd! wiring from top-level  Outputs all very low Actual lengths from top level design 400mV

Vdd! Problems  Simulation of Program Control and ROM using twice the wiring  Output correct with maximum value of 1.5 volts Doubling the wiring should halve the resistance 1.5 volts

Vdd! Problems  Simulation of Program Control and ROM using very wide vdd! and ground wires  Output correct with maximum value of 1.8 volts Extremely low resistance 1.8 volts

Conclusions / Solutions  Conclusions Vdd and Ground are not assumed to be infinite strength Vdd and Ground are not assumed to be infinite strength Vdd strength decreases as distance from pin increases Vdd strength decreases as distance from pin increases  Solutions Increase thickness of Vdd and Ground rails Increase thickness of Vdd and Ground rails Add more Vdd and Ground connections Add more Vdd and Ground connections  Status Changes were made Changes were made Simulation successful at 100MHz Simulation successful at 100MHz Need to test higher clock speeds to find maximum Need to test higher clock speeds to find maximum

Questions ?