diff --git a/api/api.go b/api/api.go
index 65336b8d..675eedf1 100644
--- a/api/api.go
+++ b/api/api.go
@@ -72,6 +72,11 @@ type TLSCertResponse struct {
 	Certificate [][]byte `json:"certificate" cbor:"0,keyasint"`
 }
 
+const (
+	// Set maximum message length to 10 MB
+	MaxMsgLen = 1024 * 1024 * 10
+)
+
 type HashFunction int32
 
 const (
@@ -188,8 +193,17 @@ func SignerOptsToHash(opts crypto.SignerOpts) (HashFunction, error) {
 //	Type uint32 -> Type of the payload
 //	payload []byte -> CBOR-encoded payload
 func Receive(conn net.Conn) ([]byte, uint32, error) {
+
+	err := conn.(*net.UnixConn).SetReadBuffer(MaxMsgLen)
+	if err != nil {
+		return nil, 0, fmt.Errorf("failed to socket write buffer size %v", err)
+	}
+
 	// Read header
 	buf := make([]byte, 8)
+
+	log.Tracef("Reading header length %v", len(buf))
+
 	n, err := conn.Read(buf)
 	if err != nil {
 		return nil, 0, fmt.Errorf("failed to read header: %w", err)
@@ -199,18 +213,25 @@ func Receive(conn net.Conn) ([]byte, uint32, error) {
 	}
 
 	// Decode header to get length and type
-	len := binary.BigEndian.Uint32(buf[0:4])
+	payloadLen := binary.BigEndian.Uint32(buf[0:4])
 	msgType := binary.BigEndian.Uint32(buf[4:8])
 
+	if payloadLen > MaxMsgLen {
+		return nil, 0, fmt.Errorf("cannot receive: payload size %v exceeds maximum size %v",
+			payloadLen, MaxMsgLen)
+	}
+
+	log.Tracef("Decoded header. Expecting type %v, length %v", msgType, payloadLen)
+
 	// Read payload
-	payload := make([]byte, len)
+	payload := make([]byte, payloadLen)
 	n, err = conn.Read(payload)
 	if err != nil {
 		return nil, 0, fmt.Errorf("failed to read payload: %w", err)
 	}
-	if uint32(n) != len {
+	if uint32(n) != payloadLen {
 		return nil, 0, fmt.Errorf("failed to read payload (received %v, expected %v bytes)",
-			n, len)
+			n, payloadLen)
 	}
 
 	if msgType == TypeError {
@@ -232,9 +253,23 @@ func Receive(conn net.Conn) ([]byte, uint32, error) {
 //	Type uint32 -> Type of the payload
 //	payload []byte -> CBOR-encoded payload
 func Send(conn net.Conn, payload []byte, t uint32) error {
+
+	if len(payload) > MaxMsgLen {
+		return fmt.Errorf("cannot send: payload size %v exceeds maximum size %v",
+			len(payload), MaxMsgLen)
+	}
+
+	err := conn.(*net.UnixConn).SetWriteBuffer(MaxMsgLen)
+	if err != nil {
+		return fmt.Errorf("failed to socket write buffer size %v", err)
+	}
+
 	buf := make([]byte, 8)
 	binary.BigEndian.PutUint32(buf[0:4], uint32(len(payload)))
 	binary.BigEndian.PutUint32(buf[4:8], t)
+
+	log.Tracef("Sending header length %v", len(buf))
+
 	n, err := conn.Write(buf)
 	if err != nil {
 		return fmt.Errorf("failed to send header: %w", err)
@@ -242,6 +277,9 @@ func Send(conn net.Conn, payload []byte, t uint32) error {
 	if n != len(buf) {
 		return fmt.Errorf("could only send %v of %v bytes", n, len(buf))
 	}
+
+	log.Tracef("Sending payload type %v length %v", t, uint32(len(payload)))
+
 	n, err = conn.Write(payload)
 	if err != nil {
 		return fmt.Errorf("failed to send response: %w", err)
diff --git a/cmcd/socket.go b/cmcd/socket.go
index c3e0c889..1e9063b2 100644
--- a/cmcd/socket.go
+++ b/cmcd/socket.go
@@ -144,7 +144,10 @@ func attest(conn net.Conn, payload []byte, cmc *cmc.Cmc) {
 		return
 	}
 
-	api.Send(conn, data, api.TypeAttest)
+	err = api.Send(conn, data, api.TypeAttest)
+	if err != nil {
+		api.SendError(conn, "failed to send: %v", err)
+	}
 
 	log.Debug("Prover: Finished")
 }
@@ -181,7 +184,10 @@ func verify(conn net.Conn, payload []byte, cmc *cmc.Cmc) {
 		return
 	}
 
-	api.Send(conn, data, api.TypeVerify)
+	err = api.Send(conn, data, api.TypeVerify)
+	if err != nil {
+		api.SendError(conn, "failed to send: %v", err)
+	}
 
 	log.Debug("Verifier: Finished")
 }
@@ -235,7 +241,10 @@ func tlssign(conn net.Conn, payload []byte, cmc *cmc.Cmc) {
 		return
 	}
 
-	api.Send(conn, data, api.TypeTLSSign)
+	err = api.Send(conn, data, api.TypeTLSSign)
+	if err != nil {
+		api.SendError(conn, "failed to send: %v", err)
+	}
 
 	log.Debug("Performed signing")
 }
@@ -276,7 +285,10 @@ func tlscert(conn net.Conn, payload []byte, cmc *cmc.Cmc) {
 		return
 	}
 
-	api.Send(conn, data, api.TypeTLSCert)
+	err = api.Send(conn, data, api.TypeTLSCert)
+	if err != nil {
+		api.SendError(conn, "failed to send: %v", err)
+	}
 
 	log.Debug("Obtained TLS cert")
 }
diff --git a/testtool/coap.go b/testtool/coap.go
index 8e9b080d..beb3b662 100644
--- a/testtool/coap.go
+++ b/testtool/coap.go
@@ -44,6 +44,8 @@ func init() {
 
 func (a CoapApi) generate(c *config) {
 
+	log.Tracef("Connecting via CoAP to %v", c.CmcAddr)
+
 	// Establish connection
 	conn, err := udp.Dial(c.CmcAddr)
 	if err != nil {
@@ -96,14 +98,14 @@ func (a CoapApi) generate(c *config) {
 	if err != nil {
 		log.Fatalf("Failed to save attestation report as %v: %v", c.ReportFile, err)
 	}
-	fmt.Println("Wrote attestation report: ", c.ReportFile)
+	log.Infof("Wrote attestation report: %v", c.ReportFile)
 
 	// Save the nonce for the verifier
 	os.WriteFile(c.NonceFile, nonce, 0644)
 	if err != nil {
 		log.Fatalf("Failed to save nonce as %v: %v", c.NonceFile, err)
 	}
-	fmt.Println("Wrote nonce: ", c.NonceFile)
+	log.Infof("Wrote nonce: %v", c.NonceFile)
 
 }
 
@@ -168,6 +170,9 @@ func (a CoapApi) iothub(c *config) {
 
 func verifyInternal(addr string, req *api.VerificationRequest,
 ) (*api.VerificationResponse, error) {
+
+	log.Tracef("Connecting via CoAP to %v", addr)
+
 	// Establish connection
 	conn, err := udp.Dial(addr)
 	if err != nil {
diff --git a/testtool/grpc.go b/testtool/grpc.go
index d23fa35d..567c0716 100644
--- a/testtool/grpc.go
+++ b/testtool/grpc.go
@@ -21,7 +21,6 @@ package main
 import (
 	"context"
 	"crypto/rand"
-	"fmt"
 	"os"
 	"time"
 
@@ -46,6 +45,8 @@ func (a GrpcApi) generate(c *config) {
 	ctx, cancel := context.WithTimeout(context.Background(), timeoutSec*time.Second)
 	defer cancel()
 
+	log.Tracef("Connecting via gRPC to %v", c.CmcAddr)
+
 	conn, err := grpc.DialContext(ctx, c.CmcAddr, grpc.WithTransportCredentials(insecure.NewCredentials()), grpc.WithBlock())
 	if err != nil {
 		log.Fatalf("Failed to connect to cmcd: %v", err)
@@ -76,14 +77,14 @@ func (a GrpcApi) generate(c *config) {
 	if err != nil {
 		log.Fatalf("Failed to save attestation report as %v: %v", c.ReportFile, err)
 	}
-	fmt.Println("Wrote attestation report: ", c.ReportFile)
+	log.Infof("Wrote attestation report: %v", c.ReportFile)
 
 	// Save the nonce for the verifier
 	os.WriteFile(c.NonceFile, nonce, 0644)
 	if err != nil {
 		log.Fatalf("Failed to save nonce as %v: %v", c.NonceFile, err)
 	}
-	fmt.Println("Wrote nonce: ", c.NonceFile)
+	log.Infof("Wrote nonce: %v", c.NonceFile)
 
 }
 
@@ -93,6 +94,8 @@ func (a GrpcApi) verify(c *config) {
 	ctx, cancel := context.WithTimeout(context.Background(), timeoutSec*time.Second)
 	defer cancel()
 
+	log.Tracef("Connecting via gRPC to %v", c.CmcAddr)
+
 	conn, err := grpc.DialContext(ctx, c.CmcAddr, grpc.WithTransportCredentials(insecure.NewCredentials()), grpc.WithBlock())
 	if err != nil {
 		log.Fatalf("Failed to connect to cmcd: %v", err)
diff --git a/testtool/publish.go b/testtool/publish.go
index 2065c16b..772a20e3 100644
--- a/testtool/publish.go
+++ b/testtool/publish.go
@@ -111,7 +111,7 @@ func saveResult(file, addr string, result []byte) error {
 	// Save the Attestation Result to file
 	if file != "" {
 		os.WriteFile(file, out.Bytes(), 0644)
-		fmt.Println("Wrote file ", file)
+		log.Infof("Wrote file %v", file)
 	} else {
 		log.Debug("No config file specified: will not save attestation report")
 	}
diff --git a/testtool/socket.go b/testtool/socket.go
index 4e8584c3..5f969266 100644
--- a/testtool/socket.go
+++ b/testtool/socket.go
@@ -40,6 +40,8 @@ func init() {
 
 func (a SocketApi) generate(c *config) {
 
+	log.Tracef("Connecting via %v socket to %v", c.Network, c.CmcAddr)
+
 	// Establish connection
 	conn, err := net.Dial(c.Network, c.CmcAddr)
 	if err != nil {
@@ -88,14 +90,14 @@ func (a SocketApi) generate(c *config) {
 	if err != nil {
 		log.Fatalf("Failed to save attestation report as %v: %v", c.ReportFile, err)
 	}
-	fmt.Println("Wrote attestation report: ", c.ReportFile)
+	log.Infof("Wrote attestation report: %v", c.ReportFile)
 
 	// Save the nonce for the verifier
 	os.WriteFile(c.NonceFile, nonce, 0644)
 	if err != nil {
 		log.Fatalf("Failed to save nonce as %v: %v", c.NonceFile, err)
 	}
-	fmt.Println("Wrote nonce: ", c.NonceFile)
+	log.Infof("Wrote nonce: %v", c.NonceFile)
 
 }
 
@@ -156,6 +158,9 @@ func (a SocketApi) iothub(c *config) {
 
 func verifySocketRequest(network, addr string, req *api.VerificationRequest,
 ) (*api.VerificationResponse, error) {
+
+	log.Tracef("Connecting via %v socket to %v", network, addr)
+
 	// Establish connection
 	conn, err := net.Dial(network, addr)
 	if err != nil {