// When - Get a buffer
        byte[] buffer = BufferCache.getBuffer();

        // Then - Buffer should have expected size
        assertNotNull(buffer, "Buffer should not be null");
        assertEquals(SmbComTransaction.TRANSACTION_BUF_SIZE, buffer.length, "Buffer should have TRANSACTION_BUF_SIZE");

        // The validation in getBuffer() ensures size is within bounds (0 < size <= 1MB)

        }

        return new byte[bufferSize];
    }

    static void getBuffers(final SmbComTransaction req, final SmbComTransactionResponse rsp) {
        req.txn_buf = getBuffer();
        rsp.txn_buf = getBuffer();
    }

    /**
     * Returns a buffer to the cache for reuse.
     *
     * Performance: O(1) operation with size limit check
     *

            // Test data preparation
            byte[] testData = "Test RDMA data transfer".getBytes();
            sendBuffer.getBuffer().put(testData);
            sendBuffer.getBuffer().flip();
            assertEquals(testData.length, sendBuffer.getBuffer().remaining(), "Buffer should contain test data");

            // Clean up
            bufferManager.releaseSendRegion(sendBuffer);

    }

    /**
     * Get the underlying buffer
     *
     * @return memory buffer
     * @throws IllegalStateException if memory region has been invalidated
     */
    public ByteBuffer getBuffer() {
        if (!valid) {
            throw new IllegalStateException("Memory region invalidated");
        }
        return buffer;
    }

    /**
     * Get local memory key
     *

        RdmaMemoryRegion region = provider.registerMemory(buffer, access);
        assertNotNull(region, "Memory region should not be null");
        assertEquals(buffer, region.getBuffer(), "Buffer should match");
        assertEquals(1024, region.getSize(), "Size should match buffer size");
        assertTrue(region.hasAccess(RdmaAccess.LOCAL_READ), "Should have local read access");

        if (minSize <= sendBufferSize) {
            RdmaMemoryRegion region = availableSendRegions.poll();
            if (region != null) {
                region.getBuffer().clear();
                return region;
            }
        }

        // Allocate new buffer
        ByteBuffer buffer = ByteBuffer.allocateDirect(Math.max(minSize, sendBufferSize));

        resp.reset();

        long k;

        /*
         * First request w/ interim response
         */
        try {
            req.setBuffer(getContext().getBufferCache().getBuffer());
            req.nextElement();
            if (req.hasMoreElements()) {
                final SmbComBlankResponse interim = new SmbComBlankResponse(getContext().getConfig());

                        // Test allocation performance
                        long allocStart = System.nanoTime();
                        byte[] buffer = BufferCache.getBuffer();
                        long allocEnd = System.nanoTime();
                        totalAllocTime.addAndGet(allocEnd - allocStart);
                        allocations.incrementAndGet();

            // In real implementation, this would receive using DiSNI:
            // RdmaCompletionEvent event = endpoint.getCqProcessor().getCqEvent(timeout);
            // if (event != null) {
            //     return event.getBuffer();
            // }
            // return null;

            // For skeleton implementation, return null (timeout)
            return null;

        } catch (Exception e) {